However, I have seen many an expat haggle with locals over pennies only to later blow a fortune on imported beer. Very sad
The most unpleasant incident I've seen in many visits to BKK was in a bar where a very ugly and overweight Englishman sat down for a beer and was then joined by a Thai girl. They chatted for a few minutes and she ordered a drink. A few minutes later he decided he didn't want her company and decided to pay for his drink and leave. I heard him loudly and obnoxiously refusing to pay for the girl's drink and (rightly I suppose) saying that he hadn't asked her to join him. The cost of her drink was the equivalent of about £2 and when it became clear that things were going to get unpleasant I suggested to him that he should pay for the drinks and then leave. He refused even when the barman warned him 'you get trouble'. A few seconds later the biggest Thai I've ever seen walked in, followed by two policemen. He paid!