Ahh Mexico! I do think non-monetary payment for services is coming back into vogue in the Canada and the US. Here in Melaque, Mexico "trade" for services is very common.
As many of you know my wife, Rosa, is a doctor. She was trained in Guadalajara and has a thriving practice here.
Dra. Rosa loves her work and those not able to pay are never turned away. Over 1000 free treatments are given every year. Half for the Mixtecas and the others for locals.