Often, it's the very same item and the only difference is whether it's purchased from the retail or food-service division. The big difference is that in a restaurant the consumer has to wait for the food; ergo, their perception is it must be fresh.
In a supermarket, the food is waiting for the consumer. Ergo, not perceived as fresh. That's why you'll see more and more "clocks" telling customers when a product came out of the oven, or was cooked, etc. Freshness should be counted in min