This must happen all the time to tourists and it could happen to anyone and it is part of our learning. We had a run in at a strip club in Soho many years ago and I refused to pay the price they wanted to charge for the drinks which was a total scam. We walked out and there were 4 of us and all well built and lucky there was 4 and not 2 or it could have got nasty as they had 2 heavies. I can see many being ripped off especially if you are in there for some time. We were in and out in less than 10 minutes and did not even drink the drinks.