I’m rewatching Spirited Away with English subs I grabbed off opensubtitles.org and I had already been confused by some phantom lines that didn’t correspond to any spoken dialogue but this scene made it obvious what was happening- there’s extra lines added in places where the characters are facing away from the camera 
Either the subtitler was hallucinating or these originate from the dub. I grew up watching a VHS tape 
in Japanese with Finnish subtitles and I don’t recall this scene having dialogue
Ah, thanks, I didn’t realize it wasn’t a text post.
Turns out the version I have only has Japanese and Russian audio. Both are silent during this scene.
Apparently the English localisation was handled by Disney. Going ham on the script sounds like a very Disney thing to do