There is a reason for that too, Paul - or at least, in my cynical old 20+ years-in-the-industry mind, I think there is a reason.
Replacing screens (or CCDs, whatever) with dead pixels costs a lot of money. So if you advertise your zero dead pixel policy far and wide, you get a good reputation but you spend a heap on replacing things under warranty. Not good.
On the other hand, if you don't have a replacement policy, you wind up with customers saying bad things about you and lose sales. Not good.
So what you do is you have a replacement policy, but you don't tell anyone about it. If a customer compains about a dead pixel, you replace the unit. That way the customer doesn't tell all his friends how bad your company is. And if a customer doesn't complain about it, you do nothing and you save anything up to $1000 or so on your warranty service costs. If, later on, that customer says "hey, I had a bad pixel" you can just say: "Well, we would have fixed it while it was under warranty, of course, but you didn't let us know about it, and it's out of warranty now. Sorry." So the customer winds up feeling that it was his own silly fault and doesn't get too upset about it, and your good name is protected.
And, if you are down in the sales department, and someone walks in saying "the shop up the road has a similar product only it's Brand X and they advertise a zero-defect policy" you can say - "oh yes, we have that too, and we are $50 cheaper".
And you are $50 cheaper, because most of your customers don't know about the dead pixel policy, and that means you only have to fix, say, one in every four faulty ones, so your warranty cost base is lower than the guys making Brand X.
Last of all, you do a little fine tuning. You never actually refuse to fix a dead pixel problem, but you drag your feet a little. You keep quiet about the policy, you don't encourage your retailers to take advantage of it, you look doubtful and hope that the customer decides it isn't really worth bothering about. (And let's face it, there are a hell of a lot of people out there who couldn't tell a dead pixel from a dead parrot.) Only if the customer seems to know what he or she is on about, and to be pretty sure that this is something that ought to be fixed under warranty do you actually go ahead and replace the unit.
The net result is that you have a prodct that is every bit as saleable as the Brand X product, none of your customers are more than just slightly anoyed with you, and you only have to replace a small number of cameras (or TFT screens, or whatever).
Seeing as this is the obvious way to maximise your sales and minimise your costs, almost everybody does it.
Except, of course, for the hordes of no-name merchants who only sell on price in the first place - for they are well aware that their customers buy on price and price alone, and, not being very bright in the first place, the "best-price, best-price" buyer is the easiest one of the lot to make large slabs of money from. You won't have any reputation left, but that doesn't matter - there are always plenty more price-buyers to flock to your shoddy in-store specials like moths to a flame, and they never seem to learn from their mistakes.
And also for the hardy few that advertise their zero dead pixel policy far and wide, then grin and bear the cost. These are usually former no-name companies trying hard to move on up into the quality market. I imagine that it's as good a strategy as any.
(Excuse rant - I plead guilty but insane and in mitigation profer my half a lifetime in the computer trade, which is enough to drive anyone around the bend!)
