Ha.  Brilliant.

Throwing Away Money At The Mall…Literally | Burbia.com:
Kid: How come there’s coins in the fountain?

Mom: People throw them in.

Kid: That’s stupid.

Mom: It’s tradition…something people have done before.

Kid: What if it was stupid before?

Mom: It’s not…

Kid: Can I throw some coins in?

Mom: No.

Kid: Why?

Mom: (pauses) It’s stupid. (mom smiles)