They're old enough to understand there are potentially serious consequences for what they're doing. I have some sympathy for police as well: the very nature of the offence makes these drivers difficult to catch in the act.
By the time an angry neighbour has heard the squeal of tyres, reached for the phone to dial police, given the details and had them passed on to a patrol car, which may be some distance away, the offending idiot is well gone.
Heavy patrolling on one problem street may only displace the problem and create a new set of angry households.
It seems ironic that this community is spending a great deal of money constructing a purpose-built drag-strip where boys can race to their hearts' content, yet we still have to put up with it on our streets.
If I lived on South Rd, I'd be lobbying hard for measures to slow traffic on the street. It's not the whole solution but at least it might slow the problem down.