I personally have not had problems with girls asking me to pay more if i stay a minute or two longer, but i must admit i don't really visit the very low budget studios. Anyway, in my opinion i do not think it is fair for a guy to stay longer than he paid for without paying extra. At the same time, it is not nice for a girl to intentionally let the time run out and charge full price for the second half hour just because the guy stayed 2 minutes overtime. Honestly the guys should try to keep track of time since it is not pleasant when a girl has to remind the guy that the time is almost up. Also if we are going to be strictly business and watch every minute it needs to specified exactly when the clock starts ticking so to speak.
This brings me to another topic, how exactly the time is calculated is usually unclear. Let's say you want 30 minutes, when does the counter start? Does it start when you begin talking to the girl? When you enter the room? When you give her the money? When you undress? After you take a shower? When she enters the room? After she takes a shower? When you start having sex? Preparations take time(showering, girl laying down fresh sheets, undressing etc.) and the question is if the client is paying for the 5-10 minutes of prep.
This brings me to another topic, how exactly the time is calculated is usually unclear. Let's say you want 30 minutes, when does the counter start? Does it start when you begin talking to the girl? When you enter the room? When you give her the money? When you undress? After you take a shower? When she enters the room? After she takes a shower? When you start having sex? Preparations take time(showering, girl laying down fresh sheets, undressing etc.) and the question is if the client is paying for the 5-10 minutes of prep.