Good point. You shoot for the center of mass and hope you can hit something.
Police has few expert marksmen. Camp Perry holds law enforcement competitions and these guys are amazing!
But the rank and file are not like these experts.
The experts are usually somewhere on call, I have never hear of any of them being involved in BLM type of shooting. It seems officers involved are often new, quite often female.
They are not even armed that well. They usually have some standard service pistol, which is east to carry, but not a competition material. Lots of money would have to be spend to upgrade every policeman on the street.
Finally, there is the adrenalin rush. It is a lot easier to aim in the range than in real world situation, if your life is in danger.