No, it was a short story in IASFM in the early to mid 80s. I think it was called “Hunger”, and I can’t remember the author. The main character was an artist who did paintings for the ceilings of the shopping mall, which (he eventually found out) were infused with the subliminal messages that made people consume more. Since he lived in the mall where he worked, he was subject to these messages all the time, and ate more and more and got fatter and fatter, until he found out what was going on and was outraged. Then he decided to hack the system and change the subliminal message to something else, something which made for a really interesting day at the mall. 