1) Selling a digital camera for a "lifetime" of use is not a good model for making a profit in the modern age.
2) It is a ridiculous, laughable idea that you will buy a digital camera for "life", until you are on the verge of dropping dead with a terminal disease or maybe you're 99 years old.
Let's say for the sake of argument that you're 40 years old and you buy a Leica expecting it to be useful to you when you're 65 years old. There is virtually no chance that you will be able to use the camera, except maybe getting it to turn on as a curiosity at a museum.
1) The memory cards and related computer readers will be totally obsolete and unavailable.
2) The DNG and JPG formats will be long gone.
3) The batteries will no longer be made, although there may be a hobbyist market that rebuilds old batteries for a high price.
4) The ENTIRE PARADIGM of storing still images on a memory device, downloading to a computer and manipulating the images will be gone, replaced by something we cannot imagine today. Doing so will seem laughable to the people living in the future.
5) Computers, needed to view and manipulate digital files, will no longer exist as we know them today.
6) Speculating a little, with the advent of "cloud computing", tightly controlled "apps", etc, etc, the whole ability to do as you please online and with your computing device will be gone. Governments will have become more totalitarian and may outlaw owning independent computing devices that are not "closed", or even outlaw creation of many types of images. (the world may not even exist, after the next thermonuclear war). There will likely be "big brother" like censorship of images and thoughts, with only politically correct and "approved" concepts and images allowed to be stored. All this is not in the realm of science fiction, they are starting down this road already. People alive now in 2012 don't have the ability to think independently and freely as people 100 years ago, and most don't even realize it, it seems "normal" to them, so deeply are they programmed. Any deviation from approved thoughts brings howls of vitriolic protests.
"Lifetime cameras" are a ludicrous fantasy.