I dislike the idea of "loot crates" even if they are unpaid. It seems silly to force us to wait to create our ideal environment. It isn't rewarding in the slightest.
I'd say the only acceptable scenario for collectibles is through unlocking them with in-game achievements that would look way fancier than the paper trophies we currently have.
Another case would be receiving game objects/models for use in home upon purchase of said game.
ie: superhot character model for getting 'red' on all the real-time trials