Sorry, I don't agree. I find this idea depressing. It is a pretty sad statement when society cannot cope with infants on airplanes and the parents must bribe their fellow passengers. (I can think of a few adults that should have bribed their fellow passengers because their behavior was not pleasant.)
Yes, some kids and adults have no idea how to behave on a flight. Instead of being frustrated, I like to think of what can I do to improve the situation. I have found by talking to kids, not about their behavior but by starting a conversation usually helps. They are excited and bored, parents are exhausted. By calmly talking to them and entertaining them - everyone wins and spending $$ on passenger gifts is not necessary!