Not read all the posts but in my town it goes a stage further. The BMX track is next to the little one's playground on our rec.... quite intimidating to not only the mums with little ones but family groups like mine and my pal's, with a combined group of teenaged girls (14 and 14), a 12 YO girl and a 13 year old lad who enjoys the loud and sometimes OTT behaviour of the teen boys on the BMX track but is family orientated nonetheless and a 6 YO. I say this even though I'm one who, like the pal who joins me in the area in the summer, is not given to being mouse-like with the boys on their BMXs who can be pretty obnoxious at times.
That, though, isn't the problem... its the young adults with their mopeds/motorbikes and cars, putting lives at risk by the way they ride/drive them in the adjoining carpark which really pee me off. They are not only dangerous but unpleasant and don't respond well to politeness and a friendly "on your side, but please can you be careful" attitude.
It really hacks me off as in all other respects our small town is great and has a better respect for others than most in my experience. Its very child-aware, having suffered a child-related tragedy which brought the whole community together but this one problem spoils it.
We have no police station in town, just a couple of Specials who operate from an office in the convenience store during daytime so the youngster's nightime driving/biking activities go unchecked. As someone who spent her youth on the back of fast bikes and who still has a lot of biker mates (and who has sadly lost some to accidents), I am upset that the youngsters on bikes are acting like nutters and not even wearing leathers but I feel that we will have to experience more loss of life before anyone does anything.
Not much help to the OP I know, but I just thought I would say that I sympathise and add my experiences.