DaCostaBR: It makes money a factor in playing the games, and the different reward tiers available create the same feeling where small rewards become irrelevant and the player must invest more and more time grinding, or more and more money, in order to achieve the bigger rewards...
Please, do not equate the game progression with tolerance. The only reason the small rewards become irrelevant as the game proceeds is because the gameplay dictates so, not because they
actually lost their value for the player in the context of the whole game. Start a new game in a different save file and after some time (or, most likely, immediately) the "less exciting" rewards will suddenly become what player wants again - otherwise the games wouldn't have the same replayability as they have. Roguelikes are a fine example of that, although they're usually not big on the whole "different save file" part :) Even getting a lower-than-the-other-character's-tier-class weapon for the new (not main) character in an MMO can be exciting, as it will be a great help on the level the player currently is with this character.
If you wish to continue the line of thoughts about the "community/social status", then this "addiction" will turn into a mere problematic-behavior-due-to-social-situation-problem. Indeed, for many the social environment - online friends - is the reason to play more or to engage in social networks more ("Facebook/Internet addiction", anyone?).
DaCostaBR: Similarly a legendary weapon...
The fact that the different things can acquire at least personal value is not debatable - it's true. Personal investment can play a big role in behaviors. But there's the difference between money and time, points and etc. - it's the difference in resources: they are not equal. While drawing parallels is possible, completely equating them ("has the exact same things") - isn't. Careless operations on money can easily create debt, and the "solution" for this debt for the gambler is obvious - to gamble more. You can't chase losses with time - the time is spent, gone, it can't be brought or gamed back (but see further). "Locked up" money or points can't be used as a mechanism to get out of debts. Spending more time on a game, compared to spending more money on bets, doesn't lead to tolerance, nor do you have a tolerance to gaming experience (do not mistake boredom for it!) or meaningful in the current context gaming rewards. It doesn't directly translates to bigger excitement out of the amount of the time spent - not like with the money bets example. And the "withdrawal" concept that we didn't really talked about doesn't fit with the gaming all that well (see the "Working towards... A critical commentary..." (referenced above), "Trajectories of abstinence-induced Internet gaming withdrawal symptoms: A prospective pilot study" by Dean Kaptsis et al. and "Craving for internet games? Withdrawal symptoms from an 84-h abstinence from Massively Multiplayer Online Gaming." by Daniel Luke King et al.).
In a similar way, gambling with imaginary points strictly in the context of the game doesn't have the same impact as gambling with real money - even if you pour money to get imaginary points.
DaCostaBR: to sell it for real money
Correction: for "Steam money". Without the third party they stay within Steam. You can create a debt with it, but not to cover it. But it's a different conversation, because again, the concept of selling stuff or a social status has nothing to do with the "gaming" that the research and ICD's item are talking about.
DaCostaBR: Working does not have the same motivation and reward systems as gambling and gaming.
I've also mentioned "masturbation" and "relationship" (you can add "sex" to that) - your example does not fit them. They also have intrinsic rewards and motivations. I would also argue, that the mentioned in the previous paragraph "grinding" can be deliberately made to be not that fun to make you spent more money on the game. From the "Craving for...":
For example, the term ‘fun’ (i.e., a common description of the experience of leisure and entertainment activities, especially games; see Salen & Zimmerman, 2004) was not reported in any of the participants' 115 responses, consistent with the view of MMO play as having similarities to paid work (Molesworth & Watkins,2014).
DaCostaBR: myriad of Skinner Box Techniques it often employs to drive up player engagement...
Media is demonizing the operant condition chamber so much, so I'm relieved that you know that it's about "engagement" and not "addict-making machines".
DaCostaBR: ...that scratch that same itch of luck and infrequent rewards that gambling does...
Maybe not "infrequent", but "irregular"? You are pointing to engagement techniques that gambling, gaming, a lot of tabletop gaming, D&D gaming and some aspects of real life share in one way or another. As you know, engagement techniques by themselves do not equal to "behavior leading to addiction".
I want to point out, that the "Working towards...: A critical commentary..." paper reports that:
However, the wording on the consensually agreed statement also assumes that problematic players will transition from one game to another to seek out more exciting experiences. The research evidence on dedicated players of Massively Multiplayer On-line Role-Playing Games (MMORPGs), as an example, would not support this notion [31]. A number of studies suggest it is the opposite, and that problematic players seek out games that make them relax, destress and/or dissociate [32–34].
In other words, we might stuck arguing about rewards and excitement when they are not even that relevant in the discussion of "Gaming Disorder"!
DaCostaBR: Finally, gaming absolutely has a "chase the losses" factor in the form of a sunken cost fallacy.
You are mixing together two different mechanisms. In the first one they try to get the spent resources back (cover the resource debt). In the second the resources they have already spent are never going back to them, fallacy or not. And no, time does not equal money here - you can't get back time you've spent. Here you talk more about an engagement technique.
Keep in mind, that the "Craving..." paper actually
does draw parallels with "chasing" in a different from yours way and contrary to my previous statements:
Interestingly, some participants provided financial rationales for extended and uninterrupted Internet gaming activity. This included the fact that the pastime was relatively inexpensive compared to other leisure activities and therefore had minimal financial burdens associated with frequent play (e.g., Gaming doesn't cost much [M, 29,Norm]). Interestingly, despite this argument, some problematic gamers referred to financial ‘loss’ associated with abstinence from gaming (e.g., Slight financial loss from not being able to utilize subscription gaming services [M, 29, Norm]) and an urgency to recover this loss when returning to the game (e.g., I have to play more to make up for lost time in taking a break [F, 31, IGD]; The break had me very invested in catching up on the games I haven't played [M, 18,IGD]). These statements suggested that, within the MMO context, there can be a duality to the perception of gaming time and virtual assets as having a certain tangible or measureable value that maybe dynamically earned and lost. In this way, gaming behavior was described in similar terms as ‘chasing’ in gambling, with the distinction being that scheduled ‘time’ (rather than monetary investment) was chased by the player.
but I point your attention that the "financial loss from not being able to utilize subscription gaming services" (note that the "Norm" means "he/she does not meet the Internet Gaming Disorder criteria") and "the break had me very invested in catching up on the games I haven't played" sound just like they came from someone having a Netflix subscription, if you replace "gaming"/"games" and "playing" with "TV series" and "watching". It's also not used the same way the Wood has described it - to solve a problem created by the behavior, to close the loop. It doesn't necessary signify chasing, as those researchers have theoreticized - and even "I have to play more to make up for lost time in taking a break" might refer to "daily quests", missed events and etc. - engagement techniques.