The vast majority of campgrounds I have stayed at do have lending libraries. Note that some, if not most, will "weed out" those that are not PG...depending on the type of campground. One's I have worked at are family oriented and we do remove (and donate locally) those that youngin's may be drawn to
I've gotten use to my Kindle, and enjoy it. Lots of books available, many free. I also download audio books that we bluetooth to our TV for the longer drives.
I agree about not watching TV. Much better to sit out, by a campfire and enjoy a good book...or your fellow campers.