We raised a couple of pigs on one sack of feed a few years ago. You must be willing to invest time and energy though, but the meat was delicious.
I asked local grocery stores if I could come by once or twice a week to pick up their produce waste. Usually they will give you a specific day of the week because other people are doing this too. Then contact your local food bank and see if you can have their old food that they would have to pay to get rid of. You will have to be sure and pick up the stuff when you agree, because they won't go to the trouble of setting it aside for you unless you will pick it up.
We built a little storage shed for all the food- bread produce, salad dressing, milk products, etc. The pigs loved it- they also had our own kitchen scrapds of course, and were on ground where they could root around.
The pork was delicious.
Susie
oops i didn't realize you were talking commercial basis.