Okay, it's two words, but still...
On my trip to CES, I was checking into my hotel and standing second-in-line. I could hear the cheerful and efficient desk clerk checking in the next guest, and when they were almost all finished, he pushed a form over, handed the patron a pen, and warmly said, "I just need your 'John Henry' right here."
To be clear, this isn't a Language Patrol situation. I didn't leap over the restraining barrier, grab the clerk by the lapels and shake him silly, crying out, "'Hanock'! It's 'Put your 'John Hancock' right here!!!'" I kept completely silent, and let life move on. Had he said the same to me when I checked in, yeah, I might have corrected him -- but he didn't. So, I didn't.
Honestly, I think it would have been fine to have given him the correct information, if done politely. For all I knew, he'd want to be saying it properly, not just from a personal standpoint, but as a representative of the hotel. Maybe he's rather hear it politely from a guest than from his boss berating him.. And in the end, accuracy is A Good Thing.
But just to review --
Guy on the left: steel-drivin' man. Guy on the right: first-signer of the Declaration of Independence.