That's funny.
I've never worked in a grocery store, always restaurants. Everything had a shelf life and nothing was re-used. Some restaurants were a little more lenient than others on what they considered "fresh".
Oh it is funny -- Until you realize that store-made chicken salad was part of your lunch

Well, at least one can rest assured that it was made from the oldest and therefore wisest chickens available.
Its similar with beef - what starts off as a full roast ends up sliced, then made into cube steak and 'steak tips' , then eventually ground beef. If the source meat is extra lean and the order is for 80% lean, 20% pure fat trimmed from the newest side of beef gets tossed into the grinder as well. Once the mixture gets pushed through three times, it gets all blended in perfectly.
The beef really isn't that old either, only a few days at most - however, the fluorescent lights in the display case, combined with settling causes the meat to discolor and become unappealing to consumers. People like it all bright red as if it were sliced off a very living cow just minutes before.
The only thing we would not treat this way was fish. Mainly because it takes very little time for fish to go from delicious to deadly.