have they tried graham crackers

For me (I use Kavita) it’s because I want to be able to just pick up whatever device is in front of me at the moment and pick up the book where I last left off even if it was on another device

Definitely, at least in the modern day. I was surprised to see Jane Austen do it a few times in Pride and Prejudice but I don’t think it had quite the same connotation back then 😆