Why will 4k/8k matter?

First, I was at the movies several times over the holidays recently and I must add that commercial movie theaters don't necessarily offer any appreciably better visual superiority over what a good 1080 home movie projector can offer, in my estimation. At the very least, the Black level quality is nothing to write home about at the commercial theaters, I've noticed. And, in fact, I've owned at least two different JVC pj's thus far, both of which out-do the black level of what I see when I go out to the movies! Thought I'd pass that on, cause that makes me feel pretty good when I use my gear at home, and am continually amazed at what quality image is available on a large screen at home from home gear!
All that, and I sit in different places in the movie theaters I go to, and get a feel for the perceived resolution at varying distances, and try to compare to see when I can see the pixels on the screen -how close I can get, etc. And I've come to think about how much of a difference these 4k images make, over what I already have at home - which is pretty impressive to me and my guests, both. And overall I just feel that the added rez at the theaters just don't seem all that much of an improvement over when I get the same movies at the house on the disc! Just sayin. I'm more than pleased with even Netflix HD at home on the big, with old technology still.
So anyway, I gotta figure that most the consumer market is already tickled pink with their Best Buy 720p 55" flat screens they got on special. So even for those who will ever dare to jump up to a bigger than 70-90" flat screen image at the home, I just can't help but wonder why 4k will really matter? That and even blown up 135+" size projected set-ups need a projector with the light output to fill the screen anyway! So, if they don't pump out higher lumens, you're limiting a solidly saturated bright image to smaller image sizes for practical purposes. That and rooms are only so big in most living rooms, and media rooms, anyway.
So I ask, why will anyone jump to upgrade, and embrace a new higher def format? I mean, sure, I'll likely take advantage in the future, as my unit starts to age. But I certainly don't see me moving on from what I have as an early adopter, just so I can sit a foot closer to my 120" I already sit plenty close to, with stellar results!
That and what I mentioned about the average consumer, who's still plenty happy with their 480/540 res DVD collection, and practical flat screens they already have and enjoy (not to mention the state of the economy), and I just wonder if another HD "SUPER blu-ray format" and unified equipment evolution will prosper?
Well, guess we'll see. My guess is they'll sell a few units, and it'll be about as popular is the draw is for 3d at present...which nobody cares so much about, across the board.
Any comments or thoughts?