I think that aesthetically, thinner looks more impressive and "cooler" so that's what sells. We're moving past it but for a majority of (anecdote warning) peop

I think that aesthetically, thinner looks more impressive and "cooler" so that's what sells. We're moving past it but for a majority of (anecdote warning) people I know, buying a phone still consists of walking into an electronics store or a carrier store, walking up to the wall of phones, and comparing the hardware and price. Sure, branding, advertising, OS preference, and other stuff has a large influence but once that is decided, they're still comparing between two or three Android phones or the big iPhone and the regular iPhone. And in that situation, even if the spec sheet lists claimed battery life, it's a number in the small print. But impossibly thin slabs with bright, crisp screens have a more immediate appeal I think. To get a real idea of comparative battery life, you almost need to do some proper research and compare battery test results from technical sites which most people simply don't do. And even then, the difference between 3000mAh, 3200mAh, and 3400mAh is just gonna be lost on most people. To make the inevitable car analogy, it's like asking someone to choose the plain looking car over the cool looking car because it gets 4 more MPG for the same price.