nothing pisses me off more than an adult thinking that a child is not entitled to be a child and expect them to behave as an adult would...

Yet it is our responsability to tell our children to care for others too. Don´t punish, just explain why they shoul be more careful... Sure, chances are that they will forget it within minutes, and you will have to remind them again and again... but eventually they will learn to be considerate to others as they grow.

And it is up to us, parents, to make sure that they grow to be respectful adults.