Steam

I agree with most of this, and I vastly prefer Valve over anything else, and as long as there's competition Valve will probably keep being the best of the bunch. I have a massive appreciation for their work on Linux gaming as well.

That said, Steam requiring that you don't sell elsewhere for cheaper can definitely be considered anticompetitive, just not anticonsumer, which isn't always the same thing. Anticompetitive behavior becomes a problem when markets consolidate and then the consumers have to pay whatever the dominant players say. Until then, consumers usually benefit (like buying stuff for much cheaper in Amazon until they make their competition go broke).