Things certainly are different here when it comes to treatment of animals. Like Gregg said in an earlier post, I've seen people try and deliberately hit dogs and cats with their vehicle. Where we live in Bayamón, it is not uncommon for boxes of puppies to be found abandoned in a construction area across from our housing unit.
In Old San Juan, the crown jewel of Puerto Rico, the stray cats are glamorized in all sorts of tourist curios and books. Walking down the Paseo and throughout town, there are many cats in rough shape. However, there's a great organization called Save-a-Gato that does what they can to help out (care, spay/neuter, feeding, etc.), but there's only so much that they can do.
Since living here, we've traveled a little bit throughout the Caribbean. It's much the same in St Thomas, St John, St Croix, St Kitts, Dominica, Antigua, and Barbados.
Like others have said, people's attitudes towards animals are different here. After all, cockfighting is still legal here.
We try to help out in any way that we can. We regularly donate money and supplies to different rescue organizations.