I think a lot of indie films are better off if they don't get into mainstream theaters. I know the producers want to recover their investment and the creative team wants the film to get the widest audience possible, but there are just some movies that need to stay small for artistic reasons. I've seen my share of indie and art films, and only a handful of them looked like a good fit in a larger theater. I don't think the same audience that came in to see machines transform into killer robots would necessary understand the subtleties of most indie or art films.
Having said that, I also think that low budget movies written with a general audience in mind should get a lot more exposure than what they currently get. It may be a question of getting movie distributors more incentive to include smaller films on the list of new releases to mainstream theaters.