It's a very good point. Your title caught my attention. We also have to remember that the whole system looks like a zero-sum game in the sense that it takes a huge investment (cash or time and effort) in order to be a whale. With that being said, it's hard for many people to see how they need minnows. Many whales (not all) seem to feed themselves with their own upvotes. Anyways, it seems to be a lot of fun to have so much voting power. It's only reasonable to limit the number of people who can attain such.