Yes, what the flavour text calls "boxes of grain" in some guy's basement have BRITISH ANTARCTIC EXPEDITION 1907 stamped on them, and having finished Rule of Rose I can confidently say it's completely incongrous with the game's narrative (though seeing these boxes made me think the plot was heading for some kind of bizarre turn.) Presumably the texture is from some big pile of old British reference materials the team used considering the surprisingly authentic old timey UK flavour the game's environments had, especially for a Japanese game from the time:
They put an actual ad for Bovril in the game 
For another great example, the REmake remaster allowed you to clearly see a ton of assets that you would've only previously seen on a fuzzy tube television, like this bottle:
The Japanese written in romaji translates to something like "Did you know? SERUM means serum. I have no clue but I think it's English. I have run out of things to write."