Most girls in RnT would love to do 30 min session rather than longer 45/60 jobs. Considering they usually get a $50 tips per session! How many 1 hr session can she do in a day vs 30 min quickies - you do the sums.
Besides, for 1 hr session, they usually have to massage for at least 1/2 hr? Which could be very hard works for some and you will get tired and with sore hands ! For 30 min, well, you should know the difference, right !
Just my 2 cents
Cheers