"Do gogoboys working in gogoboy bars receive salary from the bar, or is their income primarily derived from customers who purchase drinks, provide tips, and engage in sexual services with them?"
I have asked many go go men about this. My understanding is that most bars pay a small amount (eg 150bt) to regular men who turn up at say 8pm and stay until the close, as long as they do not get off'd. If they get off'd by a customer they lose the 'salary'. Often, if a go go man has a customer and fails to turn up the next night they will be fined the off fee (eg 500bt) because the bar presumes they are still with the same customer.