You can just use Cheat Engine to give yourself 255 keys if you really want them that badly. I tested it out with an alt, the chest drops are good but nothing spectacular. The problem is that the drop rates in the game are dog shit so people keep turning to the chest trying to make up gear deficiencies. It is not uncommon for someone to be use a decent weapon for 10 levels because they never find anything comparable. Most of the decent guns come from slots or quest rewards.
It doesn't help that killing most of the bosses results in the loot flying forth as if you just burst the worlds biggest pinata. I've seen an orange go into unreachable lava LOL. They still have not patched loot being underneath the world texture either.
I don't know, I like BL2 but there is a lot of stuff that grates on me just like the first game. At least this time its not related to the port itself I guess.