I'm more interested in the properties of the film, not that it's food grade. Most food bags are either laminates or co-extruded nylon-poly films, which gives them increased tear resistance. In addition, the food bags I have at home are embossed on one face creating air channels to bleed the air when vacuum packing.
I did find a producer of films; only problem is that he has a 3000 pound minimum and spools the product in 1000' rolls which weigh in at about 150 pounds. Not very handy. On the plus side, his price is 30-50% cheaper than the uline bags.
You must be bagging a LOT of stuff to be buying 1000' rolls