I'm not too sure how to word this as I do not wish to cause offence but I wonder how so many drunks appear to be able to board an aircraft and why alcohol is sold on board or supplied with meals even, or more especially, to those suspected of being intoxicated. Surely it would make more sense to discontinue this practice wouldn't it? As for on board duty-free sales, as I understand it (sorry if I'm wrong) all duty-free is kept locked away so why not keep it locked up until just before landing when the law of the land requires that it remain so and perhaps issue the purchaser with a numbered token in order to be able to collect is or her purchase? Even better, have a depot/counter/collection point on the ground. For duty-free purchases made in the terminal maybe a locked locker could be supplied for the duration of the flight. Just a thought or two.