If there is one thing we keep hearing from European drivers who visit the U.S., it’s that American drivers rarely observe the ‘keep right except to pass’ rule that is adhered to in most European countries. In Germany, where it is enforced rather strictly by the polizei, it’s difficult to spot left-lane campers — drivers who insist on cruising in the left lane — even absent visible police cars on the road. Of course, camping out on the left lane on an unrestricted autobahn can be hazardous to one’s health if you’re puttering along at 100 km/h and someone closes in from behind at 200 km/h. So there’s a self-preservation factor there. But there’s something else as well aside from strict enforcement by the polizei: It is considered rude in a lot of countries to hang out in the left lane, preventing faster vehicles from passing.