I think you're on the right track, only that you don't really need large grass fields available. You just need places where kids can play ball without the risk of getting run over.
I live in Uruguay and, as soon as one kid in a group has a ball, anything can be used for the goals: backpacks, bottles, or a garage door where the neighbor doesn't complain (or even better: isn't home).
There's a reason why the "Warning: children" traffic sign here has a human figure chasing a football (you can see it scrolling down here: https://www.academiadelmolino.com.uy/manual-conduccion/senal... or searching that page for "niños")
It's funny but the reverse is true here in terms of basketball in my experience. My kids like both sports and while it's very easy to find a place to play football, there are very few public basketball courts available.