Leon: Look at the look people are giving the guy. People in Canada and the US are not used to seeing armed guards away from armoured cars.
It took me awhile getting used to being searched when I went shopping in the UK (Harrods) and having guns pointed at me in Spain. (I asked a Civil Guardsman for directions and he turned towards me, evaluted me and then pointed his gun a little more towards the ground).
If nothing else a visible presence makes people aware of you and the problem.
