Poor whites, long hairs during the 60s, people who can’t fight back.
The police deal with volume and easy pickings, that is the working poor, the upper crust they don’t really like to have to mess with because they fight back, and if a department starts throwing many of them in jail like they do the poor, then all hell would break loose and lawyers and lawsuits, and in time politics would start coming down on the department.
Sadly, I suspect you’re right.