Nearly all UK uniform cops also carry tasers.

And I've seen cops in my local shop wandering up and down the sandwich aisle, packing pistols. Really, if they're on lunch-break, they could just leave the ratchet in their desk (this shop is literally across the road from the station).

Basically, if there are cops with pistols in my local shop, it should be safe to assume they're chasing an armed criminal, and that therefore I should leave not just the shop, but the the whole area.

I complained; complaint rejected without investigation by the Chief Constable (and he was pretty rude about it).