Soup factories are notorious for smells. A single pot of cooking food generally smells good, but layer up a dozen different soup flavors and in total it smells like rot.
As a kid one of the tours we did was a chocolate factory. When the person leading the tour told us the employee told us workers were allowed to take as much chocolate as they wanted we were super jealous.
At the end of the tour, there was a buffet of chocolate snacks nobody wanted to touch (though we were allowed to and did bring bags of products home), the person told us that after a day of working at the factory, most workers have no taste for chocolate snacks whatsoever, and those which do will generally fuck up, binge, get an indigestion, and at best be a lot more reasonable (at worse stop eating chocolate if it was bad enough). Without the allure of the forbidden fruit (sneaking snacks out), chocolate is definitely overpowering enough that it's a turn-off.
I did my coding bootcamp in downtown Chicago, near the Merch Mart, and (at least back in 2013) there was a chocolate factory not too far away. I remember walking to class and being almost overpowered by the smell. For awhile it turned me off of chocolate entirely, and I normally have a pretty strong sweet tooth.
I remember feeling so sorry for the people who had to work there, day after day.