They cooked over wood fires on ceramic surfaces, drank and ate from dishes made of gourds, and they even had "sippy cups" for the small children made of a gourd with a small hole in the top. Wow. Biodegradable sippy cups!
One of the other eco tours you could take was a snorkeling one at the huge coral reef at the resort. They are careful not to disturb the reef at all, and ask that you remain at least 1.5 meters away from the reef itself. They also ask that you wear biodegradable natural sunscreen if you must wear any--I never thought about how sunscreen floating on the water would interfere with the photosynthesis of the sea life, but it makes sense.
It seems this resort has everything that all the other luxury places nearby have, but with an eco-friendly aspect. There were men whose job it was to pick up all the rocks that wash up on the beach at night, so the sand was soft and smooth. They carried them in a large bag over to the garden areas, where they laid them in with the landscaping. There were fences made with rocks and broken coral between the pool and beach areas. You were asked not to feed the fish, birds, or lizards because it would upset their natural habits and it could make them sick. There were no mosquitoes because of this--that's what some of the critters eat.
Gran Bahia Principe is an awesome start toward a worldwide green movement. I was very impressed with Mexico as a whole and their efforts to preserve their beautiful nature. Even the signs along the roads warned not to throw litter from your car, etc. The Bahia Principe group has lots of resorts--look into staying at one (or one like it) on your next vacation. It probably won't completely offset your carbon emissions from the flight, but it's a big step in the right direction. And I'm telling you, the food was good!