They are busy enough serving husbands, fathers, father in laws and sons....
Do you think they got time to stand at whore house somemore when they have to wake up at 5am to prepare nasi kangkang?
it's just an extension of the buy 1 get 1 free sales gimmick - this ahpek buys 4 and gets double that amount foc. chinks have always believed that good things come in pairs, especially when it's doubled-up :p