Thread drift..... years ago (20+ years ago) my father found himself consistently receiving more attention from customs/immigration when flying into Aus. Went on for a number of flights until he finally inquired as to what the bl@@dy hell was going on.
Transpired he'd SAT NEXT to a suspect of some sort on an earlier flight! So he'd been tagged for scrutiny until they were satisfied he was clean and not associated with the other chap.
So who knows what they have on you these days. Better declare that excess booze, eh?
Oh and
brain fade - your username is unfortunately apt. That simply isn't the reason crew are forced through security. If it was actually the reason I think they would have told us by now. Clearly you are not a pilot...