Interesting Amazon/Walmart Price Match Feedback Loop

I just want to give a heads up about what I believe to be an interesting cycle in the price matching algorithms between Amazon and Walmart.

After seeing many items I've been watching steadily creep down in price by a few bucks a day on Amazon, I think I figured out what's going on.

Walmart is price matching to Amazon, but for some items they have an additional discount if you pick up in store. It looks like Amazon is then price matching the Walmart discounted price. Then Walmart lowers their (pre-discount) price to the new price, and the cycle continues until a product sells out or some other reason.

I've mostly been noticing it on many Wen power tools I've had watches on (several have subsequently made front page this week), but also noticed some Black and Decker tools creeping down the same way and for the same reason. Most of these have made all-time historical lows.

I have no reason to think this is limited to these tools, theoretically anything that is being auto price matched by both sites and that Walmart is offering pick up discounts for should be showing this price war feedback behavior.

I'm not really sure if there's much to take advantage of, but it at least explains some of the weird price behavior I've been seeing this week. Mostly, I just found this interesting and wanted to share.

For what it's worth, I did have luck getting Amazon to credit the difference in dropping prices a few days after I purchased, but YMMV on that.

Update
For those wondering when they should buy, here are some tips:
- These prices could be fixed at any time. If it's an all-time low and you need/want the item soon you're still getting a great deal if you buy now, but it may drop lower.
- The prices will drop in steps based on the item's Walmart pick up discount, approximately once per day in my experience, maybe slightly more frequently. For items with a larger pick up discount, waiting longer can pay off more.
- If you want the absolute best price (with some risk of sell out), you can wait for one of the stores to sell out and then immediately buy from the other store while the price is still low. For most of the items I've been watching, Amazon sells out first and that stops the cycle.
- If you want price protection, Walmart is probably safer, but I don't know if they will match a price that has dropped after it goes back up again.
- If you re-buy an item to get a lower price, it's portably easier/cheaper to return to Walmart then Amazon.
- Due to the mechanism at work here, at any given time, Walmart (after pick up discount) should have the same or lower price as Amazon.

Strategy Update
A great strategy for dealing with the small but continuous price drops is to buy at Amazon with slow shipping, and keep re-buying and cancelling before the order ships. This keeps you locked in at the lowest price while guaranteeing the item won't sell out on you. (See sea3n1's post in the thread below - thanks sea3n1!)

Some items that are still dropping since my post (again, for the exact amount of the Walmart pick up discount):
- WEN 6550 12.5-Inch 15A Benchtop Thickness Planer with Granite Table has decreased from $224.68 to $216.37 (update: dropped to $208.36 and now to $200.65)
- WEN 3920 16-Inch Two-Direction Variable Speed Scroll Saw with Flexible LED Light has decreased from $59.94 to $57.72 (update: dropped to $55.74)

Some examples​:

WEN 3410 3-Speed Remote-Controlled Air Filtration System has been dropping a couple of dollars a day for more than a week (see 3C). Currently, Walmart has it priced at $98.27 with a $2.26 pick up discount, and Amazon just now dropped their price to $96.11.
https://www.walmart.com/ip/Wen-3-...m/41041161
https://www.amazon.com/WEN-3410-3...B00LPD9BDI
Update: continued price drops, now at $89.91


Black and Decker 20V pole saw (LPP120B) was $72.50 at Amazon and is currently showing $72.50 at Walmart with a $2.83 pick up discount. Amazon's price just dropped to $69.67, and I expect Walmarts (pre-discount) price to drop to that within the next day as well.
https://www.walmart.com/ip/Black-...w/23569287
https://www.amazon.com/BLACK-DECK...B00AZW9Y8C
Update, both now at $66.95 as predicted.