they can if they choose.....but what cop wants to touch and put a lice infested urine soaked person in their patrol car.

Otis the town drunk and vagrant in Mayberry was lovable, and didnt stink up the sherriffs jail. But vagrants of 2018 can be covered in urine and feces.

And then the jail space is scarce. So for the folks that KJ talks about that are hard working people collecting a paycheck but living on the street.....there is plenty of violent criminals taking up the jail space.