Only if they've got lots of typos.
But seriously, I use bookmarks for paper books, but only to mark where I'm currently reading.
If I want to make actual notes, that's why Post-It notes were invented, and I have a stack of the kind with the lines. I would not write or highlight inside an actual paper book, because I like mine to stay reasonably pristine, and also, resale value considerations.
E-books get marked up more frequently, but according to the same pattern.
I'm much more likely to mark/highlight a funny/meaningful/informative passage I might want to get back to later, since you can't really flip through e-books the same way and sometimes the search function is unhelpful if you don't remember exact phrasing.
But I still mainly mark up e-books for future typo-fixing.