Dogs and to a lesser extent cats have no status in Progreso. It is basically survival of the fittest.
As you can see in the picture, they sleep anywhere. Because nobody seems to actually own any of the dogs, they breed indiscriminately, don't have owners who pick up their droppings and are sometimes a nuisance.
When you've finished eating and ready for the tab, let your server know. Mexicans don't want you to feel that they're rushing you out the door so they wait until you ask for the bill.
In addition to wait-staff in restaurants (10%) and taxi drivers (3-5 pesos), gas station attendants receive tips between 3-5 pesos and supermarket baggers receive 3-5 pesos.