Suburban blocks without fences, to my mind anyway, were always 'an American thing'. Seen on American TV programs. Here it was paling fences on 3 sides, often the backyard fenced off for the dog(and because by Law people must have safe access to your front door here), but then also you'd have a front fence. Without such fencing I honestly don't know how you'd keep a dog safe, and for the big , dare I say dangerous, dogs I would not even be happy with that much security, I'd be building or erecting an escape proof yard in the back yard, a safe place for it when I had to be away.
Scarlet does look a bit like a Pit Bull, she also looks so unhappy in the photo , poor dog, but owners of such dogs must protect them. Must keep them contained. Two Rotties got loose here yesterday and savaged a woman, no doubt they have been put down .
Stupid owners!! They make me so angry! Not an ounce of sympathy for them, but plenty for the poor dog. Incidentally, the trend towards fenceless suburban blocks has caught on in new suburbs around the City I shop in, does make me wonder if the houses are all minus pets.