Yeah but paper blows around and is hard to control in non-controlled environments. If I brought a full notepad with me, I'd have to worry about wind and humidity. A plastic device won't be as light as paper, nor as fragile.
I got rid of 600 pounds of paper this year in one go. Used bookstores got most of it. Took a couple months. Don't want more, just in case I have to move, if nothing else.