I agree with you. I don't know why Nintendo's so expensive. Do you believe many games for Wii U are still very expensive? Much more than Witcher 3 for example that I can find for pennies. That's another reason why I love my PS. I can get so much content for less.
That's completely beside the point.
But anyway, of course Wii U titles are expensive, especially now. The console was a flop, there ain't many consoles or games out there for the collectors, and, like many Nintendo consoles in the past, it's slowly getting vindicated, meaning it's increasingly sought after.
Physical copies of games like The Wonderful 101 or Tank! Tank! Tank! will certainly become rather expensive over the years due to limited amount of copies for the collectors.
The Nintendo eShop rating Thread: http://gamrconnect.vgchartz.com/thread.php?id=237454