I went down to Puerto Vallarta with a bunch of friends. We all travelled different ways as suited our lives and schedules. One gal flew through Los Angeles and called her family from an airport phone. By the time she got to PV, her husband had already been contacted by their phone company. Her code had been used for something like $5000 worth of illegal calls all over the world.
If you must use a pay phone, make sure you can cover yourself as you enter the codes. And keep in mind that those that are stealing the codes, are very savvy. They know how to watch you enter them. So your hand must be totally blind to outsiders when you enter on the keypad.

A fish and a bird can fall in love, but where will they build their nest?