I thought it was bad in France but now I live in Belgium and it's much worse. That's in Flanders, no idea about the rest of Belgium although I imagine Brussels should be worse on this regard.

People will honk just because they are stuck in traffic, and once one car starts honking, at least a few others will join them.

In my street in particular, this happens at least weekly at 7am and in front of a hospital, and if I walk up to them to tell them to stop because it's useless and disturbs everyone, they get even more angry obviously.