It makes sense that a local would hunt with any old gun he has handy.
But, suppose you work hard, plan, save, scrimp to pay for a once-in-a-lifetime moose hunt (about $5k, all expenses). Does it really make sense to show up under-gunned?
A .270 will do the job, so will a .22LR if your "placement" is correct. I'd get a .300 mag, and sell it once the trip was over.