no , you are not.
There are still bars where boy drink is bit cheaper than customer but also those where boy drink is but more expensive.
Also some bars are offering second and subsequent drink for a reduced price.
Indeed with 500 baht pricing I usually limit myself to one drink and sometimes , specially when offing boy I know I don't even offer him drink but just ask him to dress , pay off fee and off we go .
But we need to consider that boys may have quota of drinks so by being too sophisticated so to speak we may hurt them a bit unknowingly.
On my last trip when most night I had the same guy I contacted over Line without going through the bar , after three such nights he actually asked me to pick him from bar next time and specifically asked me to treat him with drink to improve his status within , at least it was what he said and I gladly obliged .