Jax, I don't see how watching the news and violence on TV would have anything to do with tipping. Obviously, these divers made an informed choice to travel to Mexico for their vacation. Why should that have an effect on the way they tip?
Perhaps I misunderstood. When you said tipping was way down, I thought it might be because there are not as many Americans coming to Mexico. This leaves a greater than normal percentage of European guests, and Europeans are not accustomed to tipping.
Now, I think I understand that you are saying, "Of all the tipping, the proffered amount is lower than usual." Is that correct?