Gift store?

As many of you know, I have the house to my self this week as my wife and kids are at church camp.

My wife and son went to the gift store today to look around, a conversation similar to this happend...

Son: "Do you have to pay for stuff here?"
Wife: "Yes"
Son: "Then why do they call it a gift store?"

I'd guess for the same reason you drive on parkways, and park on driveways.
I thought it was funny.