Sometimes I wonder if English-speaking people like to use German words in RPGs because it sounds exotic. The same way companies in Germany adopt English terms and slogans for their products, because it sounds fancy and modern.
Exoticism is a major reason that english speakers use foreign words, yes. No on in their right mind would pay 10$ for grilled flat bread with melted cheese inside, but if you call it a quesadilla (I cannot spell the word) and suddenly it’s a “cultural experience”. That said, sometimes it really is a matter of the english language not having a similar word, but in this case we usually just steal it wholesale and make it an english word. English is a bastard language, after all.
Revenant, for instance, is just the french verb for returning. It’s been an english word for ages now, but it was certainly stolen (adopted would probably be a better word, given how heavily french influenced english) initially. I find the history of english words to be very interesting, honestly.
The difference between “ask”, and “demand” for instance, comes from the relationship between the Saxons and their Norman rulers. “Demand” is (with some spelling differences, perhaps?) the french word for request. Both “ask” and “demand” essentially mean the same thing, with the difference between them being mostly in the insinuated relationship between the requester and the requestee. A Saxon would “ask” another Saxon for something, while a Norman would “demand” it. Saying no to the Norman wasn’t really an option, even if he was being very polite. :P