Rep spam doesn't sound so bad to me. It's all just fun and games regardless. Wouldn't be as bad you people seem to think it would be. Was zoklet awful because of thanks? Really seems to me you were searching for a solution to a problem that didn't exist. Oh no, the system keeps track of this fun and meaningless forum toy! That would be fucking chaos, man. Riots in the streets and stuff.
Whatever, though. You've done so much for us already. Maybe if we want to avoid rep spam you could make like a "meh" system. This way people could express their indifference even though they were never going to post (because they were indifferent). Yeah.