There really isn't a unified "webcomics community" as such. Not even among people who read way too many and hang out at news and criticism sites. And in some ways, there's surprisingly little communication between the different factions.

I also suspect part of it's due to the nature of webcomics. There's a zillion of them, so unless the comic's one somebody's been reading for years and managed to get totally invested in, it's easier to just leave it and go read something else. Because there's almost always something else out there that can give you what you're looking for. The only ones that're gonna get that kind of fanboy-ism are the big popular ones that have been around for years. There's not nearly those kinds of options in sci-fi/fantasy television.

On the other hand, I'd be willing to bet there's plenty of fanboys outside of nerd-dom. Non-genre television shows and sports would be the first areas I'd guess. Or romance and mystery novel readers. We're not as unique as we think we are, a lot of the time.