For example, in Madrid, parking is very hard to come by in the fashionable neighborhood of Salamanca. Outside of popular spots, people regularly double-park, and then go into a neighboring restaurant. When one whose vehicle is blocked in by double parkers wants to leave, he blows his horn. All who are double-parked come outside to see if he is the one blocking. If he is, the car is moved and reparked. It's a very sensible way to use parking spaces (which are dear) when the street (dear during commute hours, but frequently empty at night) is not being used.
This would never be allowed here in any town in the US. Too much common sense involved for the "law enforcement" dorks to let us do this.
We're referred to as crazy Americans. Go figure.