Why staffies..
Well, they are cheap, easy to get hold of, cheap to feed and generally economical to house.
They carry some status for some people.
IF you can for a second imagine you are a vulnerable young person living in a rough area, where members of even your own social group may be quite intimidating and you can't really trust anyone...
And you are living on a low budget in a small flat.
And going out on your own is scary.
And you probably have a stream of people wanting to come IN your flat because you've got a flat and they haven't...
And you probably have some shitty relationships and lacking attention/affection...
Then YES, a solid lump of staffie is going to be the dog for you. Fun, friendly, easy to train, intimidates the bad guys, makes you feel safe, survives on fuck all... of course you do.
And that is why staffy types (never actual pedigree staffies in fact they wouldn't appeal being far too small and not remotely intimidating compared to the longer legged, bigger, non-standard type) are much more numerous in rough areas.
I used to live in exactly such an area, when I wanted a dog the first one available was a mixed breed with a good dollop of bull terrier type in there.
At any point if I had wanted another dog, a staffy type would have been attainable within HOURS, for less than 50 quid.
Any other sort of dog would have taken weeks or months to find, a pedigree sort of dog would have cost mega money.
There are perfectly good reasons for owning a staffy, you don't HAVE to be some sort of dodgy thug to want one, but since the government decided to label pitbulls as dangerous they immediately made them VERY desirable indeed and so the staffy type became even more popular!