they don't pick up those various noises.....things like footsteps or things bumping into each other, water splashes, etc etc are all produced separately. Mics on sets are literally ONLY for dialogue. Literally anything you hear that isn't dialogue or music is artificially produced. Check out this video to get a sense.....These days a lot of the standard sounds have been digitized and they just add them in post but it's the same idea
https://youtu.be/5hWbmn7GtDE?si=alYI7M_bw94CRHqd