This proves something. I'm not sure what, but something.

That children are impressionable?

I was thinking something more along the lines of "if you believe that someone else will clear up all your mess you have no incentive not to make a mess - or even a positive incentive to make a mess if watching someone else clear it up will be interesting."

On the other hand, the Wombles, making good use of the things that they found, clearly benefited from such a mess.

So, perhaps the children thought that they were acting charitably?

Trickle down litternomics!

It means huntin' womble is harder than you might think.

Natalie's "if you believe ..." Reminds me of a young lady I knew who had spent too much time in the Chicago of Mayor Daley the First. We were walking in a park, and when I picked up a piece of litter to toss it in a trash receptacle, she said something to the effect of "Put that back on the ground! There's a man whose job it is to pick up that stuff. Do you want to put him out of work? Do you want his children to go hungry?" Gave me an insight into the way that working for the government works. If Daley had had Wombles, he would have had to send them to Wisconsin [or Narnia, or anywhere away], in order to maintain employment levels at home.