I wouldn't say weirdest, but there is a supermarket here in Tokyo that plays muzak versions of Rainbow's "Miss Mistreated" and "Stone Cold" as well as other rock "classics".
It's been ages since I've heard Muzak. I recall hearing a version of Strawberry Fields Forever at a grocery store years ago.
Nowadays, background music seems to be either old pop songs from the 60's through the 80's (original recordings) or "spa" music that seems generated from a computer program to produce the least offensive songs possible.