Bro. That's a no brainer. They do it to maximise their income. The bosses don't give them too many shifts per week, otherwise the roster becomes stale. They continue to rotate thru shops to give off the impression the girls are 'fresh'. Often the ML will tell you bullshit about their other job as a 'cleaner' etc ... in reality the only thing they're really cleaning is another blokes meat and two veg with their mouth at another shop.