Actually, with increasing number of clients, this is something I'd like to see: One client that would incorporate them all. You enter your account details for the clients you wish to use and then it would merge all your games into a single list, prompting for download and installing them via a simple script. That would be awesome.
Steam is pretty much going there. And the "increasing number of clients" is rather limited. Anything below EA and Ubisoft can't compete against Steam. Who knows what MS has up their sleeves but there isn't really more to it.
The biggest issue with Steam is that Valve is also a developer. Which would usually be problematic. But considering the amount of games Valve actually makes, well....
Yes there are laws against it... sadly tons of peoples seems to yearn for it.
No, people yearn for a hassle free experience. They yearn for good service. That is what Steam offers. A lot of people are well aware of the possible issue and include them in their calculation. They don't throw little temper tantrums along the line of "I hate Steam threads" but the public is in general a lot more engaged than some elitist schmucks might think.
I know cases were mere housewives influenced EU legislation. It only takes one angry citizen in a rule of law state. And most companies know that.