[SmG Battlefire]

1. Protection
2. Hunting
3. Deterrent to Crime
4. Protection

Need I go on??

Police can carry firearms. And in Australia, as long as you got a license, you can use that to hunt.
We're not completely unreasonable.
Also you mentioned Protection twice. We just trust our police with the protection.

Police won't always be there in that moment. The time between calling them and them being there is all lot.

"A free people ought not only to be armed and disciplined, but they should have sufficient arms and ammunition to maintain a status of independence from any who might attempt to abuse them, which would include their own government.” – George Washington

"One of the ordinary modes, by which tyrants accomplish their purposes without resistance, is, by disarming the people, and making it an offense to keep arms." - Constitutional scholar and Supreme Court Justice Joseph Story