I doubt violence would even be needed. Just the situation is a massive deterrent. The only way to move the coin means going to unknown turf, guns, dogs, cameras, unknown number of guards, more witnesses.

Kind of an I don't need to outrun the bear, I need to outrun you scenario. Criminals are looking for easy targets.

I'm not saying it can't be done to get that coin. I'm saying that it takes a more skilled and hardened criminal, realistically it takes a team.