Keyrings should spawn on Zombies and in houses and cars.
Recently i've been playing a scenario where I did not start with a keyring. Managing keys has been very annoying as they clutter my inventory. It makes sense to add keyrings as an item that can be found in the world, sometimes empty, sometimes with a car or house key, if your really lucky, maybe both. Being able to find keyrings would also help people who lose theirs or want to have multiple. As it is i've just spawned one in for my game.
Not an urgent change by any means but would certainly be nice. Lovin the updates guys, keep up the good work! <3