It is rude not to be thankful for gifts
Alex got a hat as a gift for his birthday by his grandma, but he didn't like it.
Alex wanted to get rid of the hat.
Alex thanks his grandma for getting him the hat and then returns the hat at a later time.
Alex tells his grandma that he doesn't like the hat and throws it in the trash.
Alex's grandma believes that Alex likes the hat, so she feels satisfied.
Alex's grandma's feelings are hurt, and she ends up wasting money on the hat.