If they choose to lose the benefits of having all 3 classes to max one guy, that is on them. It's not an exploit. They might level one guy faster, but they are greatly increasing the time required to max other classes because of wasted end game items. They are missing out on plenty of exotics and armor for the classes that they cant use. Xur is also completely fair, and adds just enough variety and reward on a slow week to make up for it. Pull your panties up and roll the dice again instead of creating ideas born of hate and spite for someone having more than you, or executing a better plan.