The best way to understand CPS is that they are people with crumbs of power they want to use on people, but recognize they are the lowest level on the authority chain.

So when they see a decent family, they don't feel threatened because these people won't do shit but comply and let them get their petty rocks off. And when they do break, it'll be through "legal channels" that won't do shit to them individually.

While Darren and Shaneequa will pull a gun if you enter their property, and will be giant pains in every ass on every step of the way. Its easier to just let them go with the barest minimum effort rather than try to get them to heel.