That's pretty much what a food co-op is supposed to be.
I guess I'm thinking of something like dynamic pricing, except instead of it being used to manipulate consumers into paying the most they can possibly pay, it's used to give you really transparent, real-time information about what goes into that final pricetag
There are non-coop but organic and "fancy" grocery stores in the area as well that decimate them on prices.
Admittedly, these items are all very high quality, organic, small batch, hand crafted, local, minority-owned, protecting the rainforest etc. type products, but as a single man living alone, my grocery bill would be probably $800 a month if I bought all of my food from them.
There is something to be said for the power of group purchasing power though. For instance, you can buy a cow for much less than the cost of the individual cuts and have it butchered and split for like, $2-$4/lb of meat you receive.