Bureaucratic changes and even the recent news can have an effect on airport security. In general, if you are carrying a limited number of tins or other "units," up to a half dozen or so (?) I'd guess you'd be okay in most airports. If it is anything that looks like it might be for re-sale, most of a suitcase full or a duffle with dozens of tins, then they might lower the boom, both for tobacco taxes and suspecting potential contraband, non-tobacco illegal substances being disguised in tobacco tins. But a particularly harsh security group could raise hell with anything. I once had to unpack a harmonica that looked like it might be a pistol clip, those little reed chambers lined up neatly on the x-ray, and metal too.