Its just not restaurants. Many moons ago I had a job working for a national brand ice cream company as a merchandiser/sales rep. As such I called on grocery and convenience stores and brought product from the back room freezers. I cant even begin to tell you what I observed walking through the back rooms of some grocery stores. The Safeway stores were usually pretty clean and neat and orderly but the A&P (later Super Fresh) stores were spotty some were fairly clean but others smelled like a dumpster in late July, the floors were actually sticky. In one store I saw boxes of chicken sitting outside the meat cooler - the ice it was packed in had completely melted and bloody chicken water was all over the floor and had run across the floor to the other side of the back room, soaking boxes of dry goods that were not sitting on pallets but on the floor, the smell was awful gross!
There was one store on my route a discount grocery chain I think it was called Super Foods that was even worse
OMG, I wouldnt buy Rat Chow from that dump.
The cleanest stores I ever called on were Giant, a Maryland chain. They were very well run and very clean, exceptionally clean and thats where I shopped when I lived in Maryland.
I remember a bar in Western Kansas. I actually closed it down.
It did not look particularly good in any way but I was a bit shocked when I went to the back. There was a beer tap which actually looked nice but on the other side was just a large bucket like container, open to the air tho it was in a cooler.
There was several dead insects inside the bucket.