Sometimes I rip CDs to replace music I've already pirated just for the feeling of having music I ripped myself.
Makes no sense, I know, but music is just for the feeling after all.
In some cases I have to. For example I have some classical songs ripped from YouTube that sound absolutely horrible, but I am kinda accustomed to those specific performances, and it's not always possible to find a better recording from one specific performance. And the other ones just sound... off. Sometimes this is also the case with remasters.
The worst one I have is a song from Beatles I am keeping both because it's one of the first files I downloaded when I was 8 and however weird it sounds, I got used to the compression artifacts. It's 32kbps HE-AAC at 22.05kHz sample rate. I don't even know its name. The name and metadata is in Chinese.