...I'm pretty sure the devs don't want to shoot themselves in the foot by not marketing their game to as many distributors as possible!
I understand what you're saying, but it would seem that the DRM-free approach should appeal to all potential customers who want to play the game, considering you aren't required to use any external software. Don't get me wrong, I'm super enthusiastic about my 178 (full-stop what) games on Steam because it's a fantastic service, but I'm generally happier giving indie devs with the no-DRM philosophy and -- say, GOG.com -- my money. I preordered SF because the concept, gameplay and aesthetic are what I've been searching for in a game; no DRM is delicious icing on the cake.
In other words, I've never thought, "That game looks fantastic! Shame it's only on [software], otherwise I'd totally buy and play the crap out of it." I have said this about hardware, though. Damn you Demon's Souls!
I'm not sure when the "all my things in one place" became such a desirable attribute, either. If it's on my computer where I can readily access it, I'm happy.