As usual, I firmly oppose extremes, and get all anxious-like just thinking about them.
First of all, in what other art form are commercial and indy work mutually exclusive? Does anyone say that bands that record their own cds and play shows out of their lofts shouldn't make the effort? Where would painting or fashion or film be if there weren't people out there experimenting in their own studios? In all of those fields, a lot of the indy stuff is crap by people who don't know what they're doing. But a lot of it is wonderful, much better than comparable pieces put out by Chanel or Hollywood or whoever. Some people hate the "sold-out" big names and only go with the indy stuff, and some people don't want to go to the effort to find the indy stuff so they just go see blockbusters and look at commissioned art in magazines. And that, my friends, is what makes the world interesting.
Really the only sensible position, and the one I think most people actually take, is to like what you like and not give a damn who put it out.
That's my first reason. There are more. Can you think of them?