Her interest was completing a project, so she had little care as to their reasons. I’d certainly spend a good amount of time at a shareholder meeting asking specifically that question. The remote ride reservations (the MagicPass+ ride queues) could have certainly been done using the cards as well.
I suppose in the end, they assumed they could save money by having the ‘security’ of having the band physically connected to the user, rather than perhaps someone handing over a card for someone to use. And of course, impulse buying by children, whom parents might not want to hand a card to.
In any case, the band users are spending less than the card users are spending per visitor which has Disney World on the ropes trying to justify the expense.
Disney is expert at getting money from people once they are on-site; now they are just working on keeping people there.