We must also ask ourselves, if you are REQUIRED to have a proof of purchase/receipt etc. in order to take advantage of a "lifetime" warranty, what's the point? Honestly how many of us save receipts for more than a few years on every single tool we buy? Haven't you noticed as well, that the ink on receipts from many stores conveniently seems to magically disappear or fade to the point where it is no longer readable after a few years? So who cares if I said I bought it at a flea market or direct from the tool maker's website... all I have to do is call back and lie and they should send me a new one right? Or do I need proof?
The point is, if you buy a product which has a "lifetime" warranty made by a manufacturer such as gearwrench, snap-on, wright or whoever... why would you need a receipt? I can understand retailers wanting you to have a receipt, even if they carry that brand as maybe they don't want to have to deal with the BS of exchanging hundreds of products every month from people who did not even buy them there... okay... but when you are going directly to the manufacturer and asking for warranty service on something as simple as a ratchet or wrench, that they made, which broke what is the big damn deal?
Now if a product has, lets say a 3 year warranty such as the case with a power tool, then yes I can see why the tool maker might want to see a proof of purchase if that particular tool has been in the market for longer than 3 years so that they can do a free repair/replacement. Repair services on power tools are reasonably expensive as you probably know. However, in the case of hand tools, especially chinese made hand tools this is not the case, and is why many of these products have a "lifetime" warranty. They are far cheaper to produce and cheaper to replace.
With that said, I am of the opinion that a "lifetime" warranty is worthless if you are required to provide proof of purchase... and if proof of purchase is not required, why does the customer even need to explain his @$$ off about where he bought it, when he bought it, why he bought it, how he was using it when it broke, why he didn't do xyz instead... etc etc.. If i have to be interrogated, prodded and harassed to replace a $10 chinese tool over the phone and wait weeks for a replacement IF I get one at all what is the point?
I guess all I have to add is, if a manufacturer claims to have a lifetime warranty, they better back it up in a reasonable way, or I will certainly take my business elsewhere. Fortunately I have not broken too many things that I did not consider disposable so I have not had to deal with too much of it yet. Just the thought of having to exchange something under warranty kind of makes me nervous.. just because of the harassment I had to experience once or twice at lowes and sears.