If that's the case Arsenal (and it might or might not be) then why does the basic argument about "payment" V "tip" even exist?

If we assume that prostituition is a crime in Thailand (and I've read many very strident assertions both that it is, and somewhat fewer that it isn't) then it would seem logical that anyone who facilitates or encourages prostitution (be that a brothel keeper or a punter) might well come under some degree of judicial scrutiny, if anybody was remotely interested in testing the laws.

But as we well know, very little is logical !!