Discovered my nephew doesn't plan to build the sets he asked for. Am I a jerk for not wanting to indulge him?

First off, he is a good kid. Smart and polite. He's about to turn 14 this summer. I've bought him a nice Lego set for Christmas every year since he was 8. Last Christmas he told me to wait to get his present since what he really wanted wasn't released yet (the Pokemon starter set). He told me it costs $650 and I laughed and looked at him sideways. I told him that's a lot for one Christmas gift, but if he waits until next Christmas, and skips a present for his birthday, I'd consider it. He was...