Why do my textbooks have no binding?

Question

I just picked up my textbooks and so far 2 of them have no binding holding the pages together! all they have is hole punching as if to put in a binder? Looking at them they are the only custom textbooks I have and they are both by Pearson Publishing. Is this why?

Also does anyone have any ideas on how to keep them neat? right now I just put 1,5in book rings through them but I am afraid the pages will tear