But you can say more in 500 words than some people can in 50,000, so why would you want to change that?

Look at it this way--The National Inquirer puts out how many pieces of paper with words on it a month vs, say, The New Yorker? Quantity doesn't always equal quality.

Not to say that there aren't some absolutely fabulous long fics out there, but there are also some that really could've been edited by 10-15K.

Words are weapons; wield them carefully, don't just throw them all over the place.