Move on ,Find something else
Take advise from the forum it could get violent ,farang never right Thai right
so swallow your pride move out, or offer more Money .,but do not get into a legal Battle .spend this money on an upgrade of living.
So the bar bill was less than a 1000 baht and the change was maybe 4 euro he had quite a lot to drink as many do, but to get violent over 4 euro.
The only advise here is let the staff keep the change as many do .if you live here or come here often it is the good thing to do ,
he has apologized as it said has paid the Damage
his mate thinks its a great joke but does not see the danger for escalations but over 4 euro there might be say 5000 baht or more compensation
i hope the lesson is learnt and they act like adults
jail all this other things that people are saying well maybe one day you also loose it in a bar and do the same
next day you Feel an idiot if you have a brain go back and apologies if you see the intervening copper buy him a coffee or what he likes give him 200 baht for his lunch and wish him well .
case closed .