Allow me to pile on here.
I used to believe as you do. Then I was a little down on my luck and found myself living in a poor, high-crime neighborhood. It was a shocking for me. There were cops everywhere, but they somehow never managed to help a situation.
I called the police multiple times because of violence in the area -- including for a discharged firearm in the apartment upstairs. Sometimes they showed up, sometimes they didn't. And when they did, they invariably contrived to make things worse.
I could have walked to the precinct station in less time than the police typically responded to calls. They were routinely aggressive and bullying to victims. They were dismissive of eye-witness testimony and anyone who volunteered assistance. They made open threats to anybody who questioned them or asserted their rights -- to record an interaction, retrieve their personal effects, or even help calm a neighbor in distress.
The police in that community drove around in custom cars and body armor, armed to the teeth. They hassled hard-working men, women, and even children as they went about their daily business, humiliating them in front of their neighbors for sport. They were -- almost to a man -- officious, patronizing cowards.
I moved to that neighborhood believing that police dedicated their lives to serve and protect their communities. I have several police officers in my family and, prior to my time south of the tracks, had always believed their side of the story. Criminals bad. Cops heroes.
But I left that neighborhood afraid of the cops. Far more afraid than of any of the many criminals in that community. I left with the understanding that most American police are little more than a terrifyingly well-armed gang. They have a fundamentally oppositional stance to the communities they are supposed to serve. And they are almost completely unaccountable for their actions and inaction.
So no, it's not the luxury of the rich to criticize the cops or call for a reallocation of police funds from guns to training and crime prevention. The poor have been doing it for ages. We were just ignoring them.