Thanks, it took sometime but I finally got some answer today from a Whole Foods rep:
The price tags are unclear and don't make price comparison easy between products.
According to the folks at our Northern California regional office, they have recently switched their shelf-tag system. The region is exploring options to get the unit price back on the tags and they are hopeful that a software update will do the trick.
If only ZipCar could reply the same way. I was about to open a thread on GetSatisfaction, but I lost faith in ZipCar, I don't think they are listening. I'm considering bringing my money to the non-profit citycarshare instead.