There's just too many forces at play at the tire for my comfort, even at the rear wheels. Think of a top fuel dragster, I know were only talking about a couple hundred horse in our situation but the principles still apply, without a beadlock the wheel would simply slip inside the tire of the car, that same force is applied on all wheeled vehicles but in much smaller increments but its done many more times a day. Now roughly 8000k miles later we decide to rotate those tires, now those tires must deal with the forces of cornerings which is more across the tread then down it. This process repeats itself till they reach 40k miles and you've done it without incident congrats. On semi's retreads are only legally allowed on trailers and 9/10's those giant hunks of rubber are retreads off the trailer. If you run them and feel confident doing so while saving yourself a couple bucks more power to you but I've busted my ass in the past to buy new and even used tires for my vehicles and I'll do it all over again in a heart beat. Have retreads like everything else gotten better over the last 10 years, yeah without a doubt, but unless all 4 tires blow at once, tires are not an expense that sneaks up on you over night. While they're countless positive reviews on the internet and I'm a guy that usually will try a product after I hear/see enough evidence to prove that it works but this is just one thing that I'm not exactly sold on and I doubt I ever will be.
Edit: Damn that ended up being a little longer than I expected, eCookie to anyone that reads the novel