There have been many things I enjoyed making that didn't sell well. For me I hated the loss of profit, and the product just sitting around. I made crayon book bags and loved them, my boys love them (I have one left on clearance in my shop, but have given many away as gifts). But they didn't sell well, they always just sat. Maybe because the price point was too high because of the costs and time, or because I didn't market them.
But I agree, I love real books. Although I usually have scraps of paper that my kids drew on for me as bookmarks.