Today, some gamers choose to sell their old disc-based games back for cash and credit. Xbox One is designed so game publishers can disable or enable you to trade in your games at participating retailers.

This is not acceptable. You pay today for game or any other things. And you are allowed to sell your stuff if you do not need it anymore. You can sell your iPhone, tablet, car, house, movies. And you need to be allowed sell your games too!

SOLUTION:
Allow single persons sell their games to other single persons. There is no need to limit it only for participating retailers. It is against competition! So let everyone can sell to everyone!