This was true for me until very recently.
Was a girl I had seen a few times and usually for 45 minutes to an hour, each time with a usual amount of pineapples depending on what service I took (Massage with fun).
Saw her one night for 30 minutes as that wast he only booking she had available and we had the usual type of fun.
Gave her the usual pineapples for extras and she asked for more.
Was polite, but said sorry but not this time and left.
To be fair, have not returned to see her since but have seen others.
I have no issues with girls asking but the tone and the response told me enough in this case.