Hmmm. So, you suggest that the parent, maybe, tie their little ones legs down? Beat them into submission (then we get the crying child threads ramped up)?

Now, don't get me wrong, I've been known to hold my daughter's legs down, but sometimes "stuff" happens and contact is made. Can't exactly send her to the timeout chair (or her room or wherever) while in flight. If the kicking is more than occassional and the parent(s) aren't actually trying to do something about, I can see PAX getting angry, but when the parents are trying to correct the bad behavior being a sarcastic twit at the end of the flight doesn't accomplish anything, but make the parent angry at the it's-all-about-me attitude, especially after acknowledging that the parent was attempting to correct the situation.

The DOT could certify booster seats for flight use so that the ergonomic issues could be better dealt with (but that would require shoulder harnesses and the airlines aren't going to spend any bucks for those), or the airlines could add some additional seat pitch, or, maybe, the parents could by business or first class seats (thereby starting up the kids in first class threads).

Kids have a right to travel as much as adults. Parents need to do their best - short of child abuse - to keep those little legs under control. Other PAX need to recognize when the parent is attempting to correct the situation and not be PITAs because things didn't go their way. In a flying tin can there's no opportunity to remove the child from the situation, unlike in restaurants, while shopping or visiting friends.

Now, could someone do something about the adult jerk behind me on my last flight that thought my seat back was his personal hand rail?