Anilv:
Commercial airliners are equipped with all kinds of dangerous goods, off the top of my head
-flammable liquids- a B744 can carry almost 170 metric tons of fuel. Try calling Fedex and telling them you want to ship 1 bottle of kerosene!
30 years ago a colleague handcarried a half-litre of Jet-A from a customer back to our home base for analysis. It was in a ruggedized poly bottle, wrapped in heavy polyethylene bag, in his briefcase - it probably would have withstood a 20G crash without leaking a drop.
But the young lady at security, seeing the straw-colored liquid, said "What's this?" - and said colleague professed that he raised horses, and one mare was sick, and he was rushing a urine sample to a veterinarian for a diagnosis. She turned up her nose, slammed the briefcase shut and sent him on his way!
By comparison, what about a two-litre (glass, in that day) bottle of 90-proof vodka from duty-free?