Here's the deal. Stores that sell cheese at retail want cheap cheese that they can sell at not-cheap prices, to people who don't know the difference, which is almost everyone. And they want to sell it about a pound at a time. They can't do either of those things with Grande or any other quality cheese. Grande could offer cheese in one-pound blocks, but it would be pointless. It would cost a lot more than people are willing to pay at retail level, which means it would not sell.
If you find a source of Grande at retail, don't expect it to last for long because the place selling it doesn't know how to run a retail business, and they will probably go out of business just about when you start to feel comfortable buying from them. Also, they probably won't handle the cheese how cheese should be handled, and they will likely either buy so much that it's over-aged by the time you buy it, or they will only buy one loaf at a time, from pennmac, which you can do yourself (if you enjoy paying way too much for shipping).