Agree with you here mr.sandwich, get experience first then argue your point, and if your wrong accept it and learn from that experience , it's also clear that imabot doesn't have much experience with firearms, police vehicles etc.
Many of the other weapons that police officers often carry are to bulky for use in most of the situations encountered by most leos, for short range a sidearm is quicker to draw and manuever, while rifles and shotguns tend to be more awkward to move about with due to length and over time weight, many rifle for example weigh from 8 to 24+ lbs, which can be taxing and exhaust officers, especially those of smaller stature or build, furthermore some long weapons have projectiles that can go thru the perpetrator and injure other people or items behind the perp.