@roboneko @Terry @dew_the_dew @BowsacNoodle Fortunately, that's not how bacteria works, otherwise we'd all be quite dead. The only concern with putting anything in a fridge is if the fridge is physically dirty or smelly.
If you left your cooked food uncovered in the fridge, it would dry out. The fridge is an arid environment. The fat in the food would likely also pick up the smell of the air in the fridge.