Astrophysicist here: This is caused by the moon developing a crescent shape at each end of the path, resulting in a boomerang-like behavior where the rotational velocity of the moon causes it to return back to where it was thrown.
No, it actually just appears back on the left side of the path again. No one can explain why, but it almost killed the Apollo guys. Had they been there one day later…
Of course they had to go at an almost full moon. Not much to land on, otherwise.