There is certainly a big difference between a game I'd enjoy playing and a game I'd enjoy GM'ing. Coming from a much smaller group than this, I never realized how tough it really was to find an rp you were into or people for your rps. I get ideas for characters often, and they usually just end up as npcs that I don't enjoy as much as I would simply because I hate myself as a GM. If I was allowed to roleplay under the GMerism of a similar, alternate universe version of myself, I'd be that one dude who sits at the corner of the table and goes, "Ugh... [i]This[/i] farking guy... You people put up with this?". And then I'd be cranky and ech. DMPCs just don't boil my bacon. To me, I am probably the most boring person I'll ever meet, because I always know exactly what I'm going to try and do next, even if it's me pretending to be someone else. It's infuriating that other people can have fun with their imaginary friends and I can't! :arghfist

Predictable though I am, I have made settings before that I'm very easily excited about and could probably GM for years, but people who haven't had the idea devouring their greymatter for long periods of time usually aren't nearly as excited about them, and interest can be hard to come by on any site. I guess this is kind of where fandom rps have the advantage: Everyone in it has been exposed to the marvelous idea and everyone is excited about playing it... But alas! If a fandom had the ideas I was interested in playing with, I wouldn't be toiling away at this keyboard trying to create something new for my abysmal self to explain to other people.

TL;DR: Going to an interest check feels kind of like going to a soup kitchen and worrying about whether or not you'll be able to find chicken. Putting up an interest check can feel kind of like putting up a cardboard sign and sitting at the edge of an alleyway giving everyone hopeful looks.