There's odd and end features that some people prefer with Premium. E.g. offline downloads to watch when you're out of signal, background play, etc.

And they don't want to go through alternative workarounds to do so.

For me, it's actually just being able to easily share premium with other users in my household, so that I don't have to have my ears blasted with ads when they open YT on the TV. Less effort than playing around with things like pihole and hoping it doesn't break other things.