Well, it does make sense. The rules do cost money to buy in print, and they can't just give away the rules for free on another platform. Then no one would buy the print rules. I do believe the app is cheaper than the print rules, however. And since you have to buy the print rules every year, it only makes sense that you have to buy the app every year too.
Ooohhh, that makes sense. It's just because I already get the rules for free as I'm a student not a teacher, so I didn't realize that the print rules cost money. Anyway thanks