Way back in 2012, when no one outside of Remedy knew what its next project would be, Remedy began an Alternate Reality Game (ARG) that existed within the Alan Wake universe. One collectible document explains that these thermoses promise fresh-brewed hot coffee no matter how long ago it was poured. The coffee thermoses are in the general population of certified weird stuff but they’re not so carefully quarantined.
They’re still observed and contained by the FBC, but it’s like the difference between being in prison and being in solitary confinement. Unlike Objects of Power, which are the most dangerous items touched by the Astral Plane, Altered Items have been manipulated by the “other side” but don’t seem to pose any unique threats. It’s very likely Remedy didn’t know their purpose at that time either, but nine years later, the studio decided to humorously retcon a reason for their existence: they’re Altered Items. Few could assign them purpose in any way outside of them being perhaps a reference to Twin Peaks, one of the game’s major influences. Over the years, the one variant of Wake pick-ups that never ceases to be chastised are the Oh, Deer Diner coffee thermoses. Like Control’s hero Jesse Faden, Alan Wake was no stranger to collectibles lying all around his world, glimmering for attention.