later my ad guy calls me and asks "you selling sunglasses on facebook?" I told him of course I wasn't. It turns out they had secretly set up an add to start running a few weeks later selling sunglasses. Luckily I had an add guy keeping an eye on things and he was able to catch it as soon as it started. Could have cost me thousands of dollars if no one had noticed.
Seems like a pretty easy fix. If an account is currently active, and has always been active, in a specific city then it is suddenly logged in a country halfway across the world, Facebook should probably flag that and stop that person from trying to make changes.