I like the ones who stop to wave you out into traffic, not realizing they're only one lane on a 4-lane road, so you can't go without getting hit by at least one of three other cars, and the backup they've now caused behind themselves has closed the entry window you were about to have if they'd just picked "smart" over "nice."

I'm as skeptical about the appropriateness of rules as it comes, but a surprising number of the ones around driving actually do work to make the traffic flow efficiently!