I was quite naive when I first watched this show with colleagues there, I thought the actresses/performers were forced into this profession by underworld gang club. Later, I understand this is just another job for them. Some do it full-time, some chose to do it part-time, like insurance agent job, for instance...
Of course, the business is under the "protection" of the local yakuza but it is still legitimate tax-paying business..
p/s : Just to share, the infleunce of underworld organization called Yakuza is deep-rooted into Japanese society. They are everywhere - political party, charity organization, local council, business association, etc, etc. You wouldn’t know from their appearance whether they are yakuza, can't tell from how they dress or what they do for living. I knew one of the senior managers during my assignment there is a yakuza member. Very friendly, very nice guy, speak moderately well English and well-travelled too. When I was with him in the dining and drinking places (the typical Japanese bistro at the back lane or alley, not the star-studded restaurants), I can see he is a different person in those places.