Drugged and Groggy
Very entertaining thread this. Been flying all over the world (as SLF) and heard my share of stupidity. But I ask you to consider the following: some passengers actually use sleeping pills on long flights (I do) or use tranquilizers to fight anxiety (not me, but I know quite a few people who do). Both these will cause pax to become slightly groggy and might even cause them to be unable to answer even a simple question like "Coffee of Tea?"
(Linguistically the answer to the (incorrectly phrased) question "would you like coffee or tea?" actually can be "yes"...)
Add to this a lot of pax who find themselves in a strange - and for some frightening - environment and I feel you should reconsider your qualifications about their intelligence. Although (as with CC) some will be idiots, rude, inconsiderate or clueless.
Flying with a CC that has a good sense of humor does make the flight considerably more tolerable.