Umm...they don't. Have you been watching vote times?

this is a great point. Ive never come up with a precise number, but i suspect more than half of all curation rewards are forfeited in the reverse auction.

This is one of the things like bandwagoning and list voting. If what SF thought was casuing current behavior was really causing it, most people wouldn't vote for most things before the 30 minute mark.

Part of this is a game theory decision.... sometimes voting early and forfeiting some percent of curation rewards is a better outocme than voting later (and therefore with more people in front of you). But often, its just a decision made without any rational basis whatsoever.