Oh, come on. Laptops are mobile devices that live in bags and backpacks and they break all the time. I've had more laptop failures than cracked phones, even. You absolutely need an answer for "what happens if my screen gets cracked", just ask any college student. Windows junk is cheaper, it just is.
In pre-college education, the answer is often "use any other junky Chromebook from anywhere in the world", which is cheaper still.
The very existence of the Genius Bar falsifies your point, though. The fact that you, personally, are exceedingly careful about your devices isn't an argument against the clear truth that (1) the rest of us yahoos clearly aren't and (2) macs are expensive to repair.
In pre-college education, the answer is often "use any other junky Chromebook from anywhere in the world", which is cheaper still.