The helicopter will go and respond to random calls if it’s not needed for anything in particular.
Not defending the practice, just explaining why a helicopter might respond to something that’s overkill
Sometimes it would follow you around with the spotlight until a squad car came and pulled you over and accused you of a crime which a similar vehicle was involved with. In my case, the not-me truck was illegally harvesting rock from a park, but my truck bed was visibly empty from the sky so I don't know why they bothered summon the car.
Fixed wing planes like Cessna 172s are in the ballpark of 100/hr.
About a helicopter, the problem is compounded because that whole outfit needs some quota of flying hours to remain certified. It might be a boring area, and any opportunity to take it out and fly then counts as training, if nothing else can be written up for that flight. That there is a helicopter guarantees that it will be used. And same for SWAT and such.