It was an article about a UK playlist selection company which had 6 millions yearly revenue doing this. Unfortunately I can't hit the right keywords now to find it again.
Going down that rabbit hole, I discovered some gems:
[1] Restaurant music emerges from the background - http://www.crainsnewyork.com/article/20170807/ENTERTAINMENT/...
[2] Who Picks The Music You Hear At The Mall? - https://www.npr.org/sections/therecord/2012/11/28/165947927/...
[3] Gap In-Store Playlists 1992 to 2006: The Monthly Playlists at Gap - https://gapinstoreplaylists.blogspot.com