To continue Maria's thread drift....
I'm aware that luggage rarely gets lost, but IF it does, it can be a HUGE inconvenience!
My sister-in-law's luggage was lost on her trip for my wedding. She was fortunate, as her twin was also attending, and staying at the same hotel, so she had someone to lend her clothes. Her luggage showed up a week later.
Our luggage was misplaced while travelling with a toddler. Luckily, it turned up later that night, and someone from the airlines delivered it to us. If they hadn't gotten it by the next morning, it would have meant a shopping trip for me the next day...there was no one to "borrow" from. I don't know if the airlines still deliver "lost" luggage to your home/hotel.
I'm afraid that anyone who has lost luggage once will try to do as much as possible to make sure that she has at least a change of clothes, etc in her carry-on. But I agree...some people do carry on more than I check!
(funny story...on a recent flight, one passenger was absolutely INSISTENT on carrying on an oversized box containing a Cuisinart on this multistop Providence - (ultimately) Ft. Lauderdale flight. It wouldn't fit under the seats or in the overhead, so the attendant stowed it in the front, and reminded the passenger that it was HER responsibilty to get it upon arrival....since it was multistop,and completely full, there was no way for the attendants to keep track of where people were getting off. You guessed it...she left it behind! Since it was not checked, and the lady hadn't "tagged" it, there was no way of tracking her!)