Actually, I have something of value to contribute to this, other than my usual jaded sarcasm.
When I was a manager for a retail store (before they laid me off after 12 years, but that's not important) the amount of inventory on hand was not measured so much on actual dollars worth of merchandise, but on "weeks on hand," which is to say, how many weeks worth of sales is the merchandise worth.
So if your store had an average of $20,000 worth of sales per day, and you had $980,000 worth of merchandise on the shelves and the stockroom, then your WOH (weeks on hand) was 7 (20,000 * 7 days * 7 weeks = $980,000).
If your sales fell to $15,000 per day, then you would have to lower your stock on hand to $735,000 to keep the same WOH.
In a Great Depression II, I imagine that accounting, all the way up to the CFO, would want to decrease the WOH as well, especially for retailers who are borrowing money for their daily operations. So simply decreasing the WOH from 7 to 6, with the lower sales, would reduce the inventory from the $735,000 to $630,000.
So if your sales are down by 25%, and you lower your WOH from 7 to 6, that would decrease your on-hand stock from $980k to $630k, a reduction of more than a third. Put on top of that inflation of 5%(shadowstats.com says 10%), which means that each item of the shelf costs more dollars per item, and you're darn near to 40% fewer items on the shelf. So where there used to be 10 cans, you would see six. If sales are down more than 25% in a particular store, or the reduction in WOH is more than 1/7 for the chain, it may be more.
You will probably start to notice soon that your store will begin eliminating less popular items, especially those that sell less than one unit per quarter. The way that happens is that when it sells, they simply remove the sticker on the shelf, and make the item next to it fill the hole. When this is done enough, the next step is to eliminate the number of shelves on the aisle, and/or increase the space between shelves. That way they can continue to stock quantities of the most popular items.