I'm against it because I don't have a smartphone. I'm against it because I personally prefer hard copy over digital anything. (Books, music, movies, etc.). I do have an iPad and can do onlijne research--and yes, I recognize how incredibly valuable that is--but too much of it gives me severe headaches.
And finally, the historian in me, old enough to have seen the troubles we're having in accessing materials stored on now outdated methods of storage, worries about preservation of knowledge decades and centuries from now if hard copies vanish. My first cousin recently sent me an album of 200 pictures of our dads and grandparents in the 1930s and 1940s--a treasure. In contrast, daughter takes hundreds of digital photos of my granddaughters each year. But will Cordelia and Phoebe's grandkids be able to access them one day?
By all means, we should conserve resources. We should recycle and reuse. But along those lines, paper is a good renewable resource.