Exactly, that is comparing apples to oranges. In one of the companies I was in we started charging $5 for being late to a huddle or $20 if you were an exec - people took cabs to get to the huddle on time, because it was the fact that you had to pay, not the amount that motivated you. Cab was more than a fine.
When you think about how people respond to incentives, first consider the size of the incentive. Otherwise you'd be forced to conclude that, say, a $10,000 fine wouldn't work either, which is plainly absurd.