No....The whole point is people don't have to pay if they don't want to. So they can win even if they never contribute a dime, its their choice. I would even consider throwing out the idea of making contributions, but I figured it was an incentive for people to help more often, in order to become member of the month.
I think it is more generous if someone contributes knowledge in the forms than money.
Now I definately think that a person should only be elected once. That way other people can have a chance.