I believe their reasoning is much the same. They have some types of tickets, which can technically be handed over to others and abused. Think weekend ticket, where you hand the tickets to someone else for them to use on Sunday, or tickets that can be converted to season passes, if you do it the same day.
Blaming scalping doesn't seem entirely plausible to me, because there was always the option of making the tickets and season passes non-transferable. There are other methods. Especially if you're only issuing paper tickets as an alternative, e.g. yes we will sell you a paper version, but understand that it is absolutely non-transferable and non-refundable.
Some people might not want to bring a phone to these types of events and venues, which I can completely understand, neither do I, but I can live with it. The thing that bugs me is the lack of an alternative, which isn't really that expensive and which most won't even use. Because to some, the app really don't provide value and in those cases they solely exists for the benefit of one company. If you're paying the price of season passes to pretty much anything these days, I think you're entitled to some small level of personalized service and customization.