With TV series, usually you have no choice but to wait for the next episode to be broadcasted. However, with books usuall you have a complete book in the hand, why to put it away and start reading another? I mean if I could, I would not wait for another episode for a week, watching different serials meanwhile, but I have no choice. When I read a book, I do have a choice
Moreover, 99% I never watch serials that show 1 episode per week. I would record the whole serial and then watch it all together