^ I would guess that if AutoZone's buyers cooked up a deal with another vendor to make "Duralast" brand tools they
quite possibly also got them to buy back any "warranty" units that were manufactured by the previous vendor.
I did that with several vendors - particularly rebuilders (starters/alternators/generators).
Sometimes they'll do it for a limited time period, after which the retailer (or wholesaler, as in my own case) eats the warranty returns after ** months/years.
And then there's always the option of the vendor/manufacturer just giving the buyer an off-invoice credit of **% to cover warranty returns, and the retailer (or wholesaler) just throws the stuff in the garbage. (That's how Westinghouse and Sylvania both dealt with "warranty" on bulbs.)
There are all kinds of ways to make it work - we still honored the "unconditional lifetime warranty" on Indestro after we dropped the line and switched to Thorsen, but it was along the same line as what Sears has done: we replaced the Indestro item with Thorsen.
The Thorsen sales rep also sold us Buss Fuse, Master fuel pumps, Carol Cable, and several other lines, so we always managed to finagle a deal with him.
My point was that neither AutoZone or "Duralast" are
forever. Retailers come and go, the same as manufacturers and brands.
Not sure where "the valley of the sun" is, but odds are you probably once heard of a place called Schucks or Checker or Kragen Auto Parts, right?
Or maybe Al's Auto Supply?
==
But more to the point:
You guys looking for wrenches - unless you're adamantly opposed to the idea of "used", keep your eye on this thread:
https://www.garagejournal.com/forum/showthread.php?p=6937100#post6937100
Maybe it's the time of year, or maybe it's just my skewed perception, but I am seeing a
lot of listings every day lately for used/slightly used primo quality wrench sets.