I'm curious, were these bolts/screws the ones holding the cabinets to the walls/floor, or somewhere else inside the cabinets?
It's now a habit to check the drawer slides once a year after noticing one time that my top drawer wouldn't close square because the (filing cabinet style) slide hardware was loose and screws had backed out quite a bit. But(!), I haven't been looking and checking anywhere else and a few times I year I drive through Oklahoma and Arkansas on their extremely bumpy roads... So I'm concerned now.
Larry