Light source for glowstick isn't located at the center of the glowstick.

[veryjos]

It's located lower, near the wrist of the player:

Ananas4 on Reddit:
Okay figuerd it out, the light source of the glowstick is at little further ahead than the actual stick? Don't know if this is intentional or not, but that's what caused it, the light was under the shelves even though the stick was in front of them. You can also see it when you rotate the stick and the shadows move weirdly. Here's a clip of me testing it out.
https://a.pomf.cat/dvooqv.webm