If they only needed ONE book, that would be reasonable, but they need a $5 book for EACH merit badge, which is unreasonable.  So even if they own their own device, to have to pay $5 every time you start a new Merit Badge can add up pretty quickly.    
Online or app availability is a good idea too.  I hope they really are working on that, but they do seem a bit slow to keep up with technological advancements.  They could have the Eagle Required available as a package and then offer the others at a low price like 50 cents or a $1 each.