What´s cooking?

I had an interesting cultural interaction today. I´m lucky to have one of the two directors of the school as one of my 2 teachers. This morning, he (Romeo) looked a little agitated. It wasn´t long before it all came spilling out.
Yesterday was our "cooking class" day. Lupita, the young girl (20 to 25?) who is the combination receptionist/bookkeeper of the school is justifiably proud of her cooking skills. So she was the one who taught us how to make mole. I had asked her a couple of times before the class how much it would cost. She got very embarassed and said she would buy all the ingredients first and then afterward, we could divide up the cost. I don´t think any of the other students even asked. One told me afterward that he just assumed that this cost was covered in the cost of the tuition.
This morning Romeo told me that Lupita bought food based on the number of attendees. One European student came in, saw the chicken in the pot, announced "I´m a vegetarian," and left.
We spent about 2 hours cooking and eating and talking and having fun. The mole was absolutely delicious and I kept thinking of various ways to make a vegetarian option out of it. The others took off. I again pressed Lupita how much I owed her and she said very diffidently, about $3. Big spender that I am, I gave her $4. It seems no one else paid her a thing, so she was out of pocket about $15, which is a lot of money in Chiapas.
Romeo asked: "How come the gringos (north americans and europeans) don´t know to pay or to leave a tip for her time?" I told him he´s dealing with gringos. He has to come out up front right away and tell people "The cost of the cooking class is $_____" I told him he should make the price high enough to cover all eventualities and include something for Lupita´s time. We gringos are going to pay it, whether the price is $3 or $10, because it´s all part of the learning experience.
He told me his school has been open only a year and a half. He hired away the best teachers from the other schools. There´s a small handful of language schools here in San Cristobal, all the others owned by gringos and run accordingly. For that reason, I´m sure he had no trouble at all hiring teachers. He said he and his partner decided from the beginning they want to be as nice ("amable") as possible to the foreign students. So there´s a donation cup next to the coffee pot and both are always empty.
I told him he has to write down "rules," and discuss them with the gringos when they first arrive, etc. How much coffee costs per cup; how much the cooking class costs, salsa lessions, etc.
He looked very dubious. To be so gross and in-your-face about money matters goes against every grain in his body. He said he and the teachers have been discussing this problem for over two months (!) and that they were going to have to take some sort of action pretty soon for the sake of their employees. He obviously looked very uncomfortable about having to do something so contrary to his social upbringing.
It´s kind of sad. He wants so much to teach and he is an excellent teacher. But he´s going to have to learn how to deal with gringos if his school is going to survive.