I should have been more clear in the final paragraph. I didn't mean you don't own the physical copy of the book. I meant you don't own the text itself. Rephras

I should have been more clear in the final paragraph. I didn't mean you don't own the physical copy of the book. I meant you don't own the text itself. Rephrasing: It's a distinction without (much of) a difference, since the paperback will outlive you and probably your grandchildren, but [the paperback is] not eternal, and so technically you don't own [the text of the book], the same way you don't own [the text of the book when you only have] digital copies. The time frame over which you don't own [the text of the book] is just longer.