Sorry, I just don't see this as beneficial. Unless you're willing to have some people go through the lines with things that should be confiscated on a random basis, if people play by the rules, then there will be no bonuses paid. And it will be totally random who gets the bonus.

This isn't a sales job, where your work leads to the sale which leads to your commission check. There, a bonus plan makes sense.

Here, it's so random that it's really not going to be an incentive in my view.