I'm not even going to lie, I kinda want one. The purpose; not really sure. Basically its a, why not have one? I would probably use it as a truck gun as I've got loads of 30-30 ammo. Make fun of me all you want, I've been a noob on other forums, I can take it.
Now the whole Zombie ammo thing, that's another story...
Edit: why does a .22LR need a muzzle brake?