You would be paying for the hardware which is pretty good (as long as you can accept the downsides, most notably that it isn't upgradeable nor maintainable, and Apple charge an arm and a leg for memory/storage). It'd be like buying a laptop that came with Windows and installing a Linux distro on it. Why not? If you're more comfortable with it that with the base OS, even better that there's choice.
You can not get a similar Windows laptop for half the price. That is absolutely ridiculous. Show me a single Windows laptop that has a similar screen, keyboard, trackpad, build quality, processor, battery life and silence. I'm waiting.
the new Dell XPS is just one example, ticks all your boxes. If you think nothing compares to Mac you clearly haven't been paying attention to Windows laptops.