Firsts: Sign of Madness?

Although I've picked up a few along the way - mostly from charity shops, fetes and suchlike, back in more innocent times - I've never really seen the point of modern first editions. Why on earth are they worth so much? And why is condition so ridiculously important? Take this collection, expected to fetch a cool million at auction. They're worth that much because their owner has never touched them - to handle them, let alone (heaven forbid) read them, would knock hundreds or thousands off their 'value'. But in what does that value reside? Purely, is seems, in their primacy and their untouched condition. It's nothing to do with the beauty (or, often, otherwise) of their appearance - a later printing of a modern first would be identical but for a different number on the reverse of the title page and yet would be worth a tiny fraction of the value of the 'true first'.
I can understand the appeal of collecting well made small-press books, and pre-Victorian books - these are things of beauty in themselves, hand-made and a joy to handle; indeed (gentle) handling is positively good for leather bindings, helping to prevent them from drying out. But a book that doesn't look like anything much, is entirely machine-made, of pretty poor quality, won't last, and that you can't even handle - what is the point of that? Surely this form of collecting is a kind of madness.