Why do Nintendo game prices never fall?

[Mystro-Sama]

Seriously, i've always wonder this. Even months after a game has been released it still maintains it's release price, and even if it does fall it only falls by like $5.

Like WWHD which is $50 on Amazon:

http://www.amazon.com/Legend-Zelda-Waker-nintendo-wii-u/dp/B002I0GF72/ref=lp_4924901011_1_5?s=videogames&ie=UTF8&qid=1424212423&sr=1-5

Or Tropical Freeze which is still also $50

http://www.amazon.com/Donkey-Kong-Country-Tropical-Freeze-Nintendo/dp/B00DC7O77A/ref=lp_4924901011_1_11?s=videogames&ie=UTF8&qid=1424212485&sr=1-11

And unless no one has noticed the Wii U isn't exactly in the best position.