I worked at a high-end gym/spa like that once. They tracked their secondary spend very closely. Staff were trained to upsell at any turn, from personal training

I worked at a high-end gym/spa like that once. They tracked their secondary spend very closely. Staff were trained to upsell at any turn, from personal training (why don't you buy the 3 month package ma'am?) to drinks (we have this brand new smoothie and protein bar, have you tried it?).