Valve has a history of releasing the best product on the market at the time, then iterating in whatever ways they want, regardless of what competitors are doing.
But this basically hits right at the core of my GAF annoyance (not aimed at you directly BTW) - let's just say in some mythical universe, EA became a super consumer friendly totally awesome gaming company with the best DD client around? In that (yes, unlikely) scenario, GAF would still be clinging to Steam because whether it was true or not it would be regarded as "the best product on the market at the time".
Blind devotion to anything really bothers and rankles with me. So called "good" companies can turn evil at the drop of a hat. There's precedent: Apple did it, SCO did it, Google appear to be doing it.. who's to say that Valve won't suddenly become amazingly anti-consumer and alienating ten years down the line? Is it likely? Probably not. Is it possible? Absolutely, because Valve at the end of the day are a business, and first and foremost a business will do whatever is in it's interest to make money.
We cannot assume that just because Valve and Steam are harmless now, it won't remain that case indefinitely.
And that is the reason that I don't really make a distinction between Steam, Origin, Impulse.... hell even Onlive and companies like blockbuster or netflix. You're basically paying for a right to play that game and it is not a permanent right. In fact, it's more akin to a rental system than a purchase system.
At least with GOG, you have the game on your system locked away and nobody can ever take that away from you. With Steam et al, all it takes is for one legal challenge related to the most obtuse of reasons, and Valve can pull the game off the servers, and you'll never see it again, with no recourse to get your money back.
In my (twisted?) logic, if digital distribution is the future, it's only really viable in the long term if we can actually keep the titles we have paid for in some local form. This is why I'm pro-GOG and ambivalent (but I stress - NOT AVERSE) to cloud based DD methods, such as Steam. In addition, for me, having Steam as a "default setting" is a worrying precedent as no one company should be the "gatekeeper" for an entire format's output. Atari tried it, and failed. Nintendo tried it, and failed. Sega tried it and failed (in fact that's where EA came from - making at the time "unauthorised" cartridges for the Genesis). Look at the barrel that Apple have the music industry over with iTune's lock-in and dominance for an example of why this is a bad idea.
In short: Competition is good, because it keeps everyone, INCLUDING Valve in check. The existing DD method is not a purchase opportunity but a rental opportunity, and one that is unlikely to stand up when it inevitably gets it's first trial in a court of law.
Lastly: Google and read up on re-digi. It's a landmark case taking place now that should go some way to defining the law in terms of digital content ownership. It points out some key contradictions that currently exist with the current digital distribution models for music, movies, books and games, and will clarify exactly where the consumer stands in terms of rights of purchase and resale. If the courts do rule in favour of a consumer, Valve could be potentially liable to introduce a method to allow a consumer to re-sell a digitally distributed game. Do you think they will in that circumstance, or do you think they'll just change the wording of their TOS to "re brand" as a pure games rental service?
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. We don't currently distribute Blizzard games digitally.