Originally Posted by
irishguy28
You're overlooking the fact that they also don't want vessels of any great size on board, into which the contents of many (legal) smaller bottles can be decanted, to concoct a greater volume of a dangerous/unstable/toxic liquid.
I've never been stopped with empty bottles (like a good hippie, I return my empties for "pfand" where relevant).
Amusingly today I'm flying with a Klein bottle for a friend in my carry-on. Mathematically it has zero volume, but try explaining that one to the security droids...
(Incidentally, first "Flynet" flight this year!).