There's heartbreak every time I go overseas to visit because in Greece strays are very, very common.
For the most part they aren't anyone's pet - although many people let their dogs out freely but still feed and they sleep indoors at night - but they are just... there, a product of very few shelters booked to capacity and very few folks fixing their actual pets ("I don't want to take the joys of mother/fatherhood away" is a common stupid thing people say).
Some of them, especially in the tourist season, actually have okay lives. They get food handed out, there's lots of garbage they can plunder, it works. But over the off-season, or in busy or industrial parts of big cities, they are really screwed. They are too friendly or too scared (I don't even know what's worse), sometimes obviously starving since you can see their ribs. The bigger ones are in trouble so you see fewer of them - they require more food, after all, but also people are more afraid of them so the chance of being taken in by someone are less.
It's the whole culture there, too. I've spoken to people who had others imply (or state) they'd poison dogs if they barked and disturbed them and the police can't act on allegations alone, plus it's damn hard to prove who did what after the fact. It's just such a mess.