According to a story in the Washington Post, this animal is a stray dog in Athens. This one hangs out outside a 5-star hotel in Styntagma Square, but the rest of the stray dogs shown in their photo essay look nearly as well fed as this one. One picture shows a man feeding a stray dog "leftover bones and meat."
I may have to revise my picture of how stressed Greek society is. I mean, a society has to be pretty rich to have stray dogs that look like these.