Speaking personally, I've had Windows laptops that have had a touchscreen and I've really enjoyed being able to scroll through a webpage with my thumb at the side of the screen. Being able to easily sign secure documents with my finger tip has been useful too (ie I actually did a decent version of my signature). Small use cases I now, but I still found them nice to have.
I would imagine the extra cost to build a touchscreen into a laptop is minimal now with the tech being mature, so it's not going to be adding a huge amount to the purchase price. Apple has likely done their research and concluded that enough people would like a touchscreen to make it a worthwhile business decision to employ, along with MacOS becoming more aligned with iPadOS (and vice versa) over the years to make the UX & UI interactions more fluid too.
Most people seem to cope with finger prints on phone and tablet screens okay, I would think the larger part of the Mac buying population will be the same with finger prints on their laptop screen too. Obviously there will some who would prefer a pristine, fingerprint free screen, and that is totally fair enough too
To be honest, just like the video functionality in 'stills' cameras. Just don't use it if you don't like/want it.