Belgian here - I do tip but as mentioned elsewhere in this thread, it's not part of our culture. And I leave mostly small tips, nothing comparable to the US.

I once paid a tenner with €5 due and left in a Belgian bistro. I was followed and forced to take back my €5 as they didn't consider tipping appropriate.

Never had that happen to me - but what I did encounter is that it is explicitely stated that tipping is not necessary and that the service is counted for in the bill.

But those are unique instances I believe :-)

Nonsense, tipping happens all the time in Germany.

In general, there is a north-south divide, but I guess it also depends on your milieu.