Literature isn't art. It's literature. Yes, it's a form of expression, but it shouldn't be classified as art---hence the name literature. I'm an author too, I'm writing a novel right now and I'm only a hundred pages in. But For Unique-Imaginative, I want to keep it visual.
To me, writers can find other groups to submit their work and other websites to do the same. If they are truly committed authors, they should be looking for publishers, not a deviantART group to submit their writing. The part about you saying becoming more popular and earning more members, doesn't matter to me if I have to give up a rule that my group depends on. I'm sorry if you disagree, but maybe this isn't the group for you.