His latest fascination in Billy Mays and all the products he sells. "Are they really that good?", "Why don't we have that?" and other questions that show the child is thinking beyond the 'buy me this' impulses that the commercials instill in people.
I came up with something to observe. My explanation is that the more excited that a person pitching a product is, the lousier the product. The product should be able to stand on its own, without some person foaming at the mouth with his excitement.
The lesson about people getting suckered was no sooner given, than I had a customer show what happens when you're not astute. They told me they bought something elsewhere because they got it half off. They didn't wonder why the item costs more than twice as much as any of their competitors. (inflated price for your bargain getting pleasure). It's probably good that we're talking about these things with our kids.