Noodnik - good of you to stick it out and put up with the narrow-minded comments above. I suspect there are not many airport security staff who frequent here, for several reasons.
Millerman - a few too many unknowns in your post, I feel?
Going through security at MUN: often happens when changing airlines, where your luggage is not checked through or where the screening is at the gate. It is not unusual to have to go through 2 sets of screening at some airports.
Was your purchase in containers of less than 100ml and 'presented' in a clear, sealed plastic bag? If not, you really cannot complain.
Noodnik answers another of your queries at 2
Answer 3: I'm fairly sure that some of the 'decisions' made by crew (in accordance, of course, with their orders/instructions) might annoy Noodnik if he/she were travelling as a pax. <and they're not allowed to use common sense or they get their a***s kicked.> - bit like crew, really? "No sir/madam, you cannot drink your own alcohol". Is there any point in Noodnik having a spat about that?
NB: Not directed at Millerman
No, it is not fun trying to operate in this environment. Yes, I would like to see more rapport and humanity in screening, but it is not going to happen, and shouting, screaming and kicking toys out of prams will not help.