Whoops. I didn't understand what you meant the first time.
EW_BEAM and EW_MAGIC both seem to share the rotated hitbox properties. At a guess, I'd say that this is either what makes them hurt Link, or is just that LW_REFBEAM and LW_REFMAGIC are basicially generated in the same fashion.
Either way, looks like this may not be a bug after all; just an oddity.