Commercial entities (kindergartens, schools, etc.) present themselves as well equipped by showing they have well equipped playground or other amenities. Those are filled quicker than those not having one and I've seen instances where few commercial entities decided to create a shared commercial playground. Some are pay-to-enter so it's even simpler.
Public ones are more complicated. I know for instance, that where I live there are annual calls for social projects which are voted upon by community and payed for using tax money. There's plethora of them and while budget for the winner projects is limited quite often there are groups trying to push their idea even if it fails and lobby for them. It of course affects local politics and activists which are trying to make various ideas happen.
It's not perfect, and sometimes it fails. Arborists are doing periodical inspections yet there is always room for error. Inspections won't prevent strong wind from breaking branch off) but it usually keeps thing together.