More anecdotally, I've seen quite a few stories of people who called police for fairly routine visits that ended with somebody getting shot, after the police escalated the situation.
No, the thing is that violent encounters with the police are reported by the media, and nonviolent encounters are not, because they're not news.
Based on reporting, one could also assume American blacks are violent thugs, Muslims are hate filled radicals, and all the Jews in the world are in Israel.
Thing is, your example fits in with "the natural order of things". No one is surprised that some members of a general group of people are "violent thugs", since there are people who are like that. Ditto "hate filled radicals", and there are observably many Jews in Israel, it was established for that exact purpose.
Whereas there's a mainstream theory that police are there to "protect and serve" the non-criminal population in a Western nation, it's not supposed to be in the natural order that they're e.g. observably eager to kill your dogs given the slightest opportunity.
It's very counterproductive, to the extent they in theory exist to preserve order, it deprives them of vital information. It's extraordinarily short sighted to behave that way, for so called "good cops" to look the other way when "bad cops" do that, in a thoroughly armed society they have no hope of disarming.
You're making the wrong inference from this, I think.
The thing about news agencies, and journalism in general, is that they generally report on rare or unusual incidents. If Americans were regularly getting shot as a result of calling the police, it would be commonplace, and thus no longer newsworthy, so you would not see these stories.
