so someone is stealing money from customers? hmm

If you had read it properly, you would have realised that the comment was for you, kiddo. The clue was in the use of the word "your" and it was explaining why "you" as a purported resident of Montenegro might never have seen the fees "you" were charged (assuming that "you" were being honest).

But as you have asked for me to relate this back to the US, as the final word on this, I refer you to the following website that explains how all this works and is even a US website.

https://www.valuepenguin.com/credit-card-foreign-transaction-fees#:~:text=A%20foreign%20transaction%20(FX)%20fee,to%203%25%20of%20the%20transaction.

From this point on, it's 2022, so feel free to believe what you want, but given the information available, we've got to the most likely answer. As you said previously, there's not any point in any further speculation.

My boy, just drop it. Take a chill pill, take some tea and move on.

There are, if you link your credit card to Paypal. Because the credit card company or the bank is the one who charge the fee. And for them it doesn't matter at which service you use it.

It all depends on what ToS the credit card or the bank has.