This case has nothing to do with the law enforcement's competency or niceness
The police can't prosecute unless you can ID the driver.
I witnessed a hit-n-run on a parked car so the day afterwards I dropped by the home (this house had 4 BMWs, and it was a 650 that I got swiped) to tell him what I saw, the license plate number, etc.
He filed a collision report with the police and the rough estimate for his repairs came out to about $1K --but because it was at night time and I didn't get a visual on the driver, the license plate alone wasn't enough to press charges, since without a proper ID on the driver, the other party can deny being the driver even if the vehicle is registered to their name.
And the owner of the BMWs even had a buddy at the local PD.