In Mazatlan for an experiment in leisure travel (the experiment was an alloyed success), I paid for a set taxi at a walk-up kiosk at the airport to get to the resort area. Chatting in Spanglish with the driver on the way, I said I had heard of the local golf-cart-style cabs called pulmonias, and I wanted to know from him how much I should expect to pay for one. He said that the usual fare is 40 pesos -- drivers will ask for more, but they typically get 40.
My experience was exactly thus -- I would hail a pulmonia, tell the driver where I wanted to go, he would say it is 60 or 80, I would ask if 40 is ok/enough, he would say yes, and off we'd go.
A few days in, I was climbing down from the lighthouse as the cruise crowd was just making its way up, and I asked a north American couple how they had gotten here -- the man said that there were plenty of golf carts waiting at the dock, that the driver said it was 80 pesos a ride, so "when we got here I just gave him a 100 peso note and told him to keep it". Seemed like a good deal to him -- about US $10 for a cab ride for two people.
This incident flashed in my mind this morning when I read the article here on RS written by Rick himself about Ugly Americans abroad, in which Rick explicitly says that overtipping calls attention to your affluence more than it helps the local situation.
The cruise vacationer who pays more than double the going rate (I'm under no illusion that the 40 pesos I was paying was any kind of hard bargain) is throwing the system off balance, don't you think?