This seems like it has a lot to do with psychology. Laura asked why it might increase AP sales. I would say because people see $30 a month, and believe they can afford that easier than a lump sum of $380. And as skyndave said, either you can save for 12 months, then get a pass, or just get a pass today, and pay it off for the next 12 months. Purely a personal preference, I do not think it implies anything about one's intelligence, or lack or, or ability to save, or lack of, or anything of that nature.
I'm not sure I will ever understand most of the topics on budgets, prices, monetary issues, as anyone here is in a financial situation well enough to even think to go to WDW each year. It seems the majority go multiple times per year, hence this AP renewal topic. Why should we argue over such a topic, when it's pretty obvious most of us can afford a Disney trip without too much worry about feeding the family? Just my two cents.
EDIT: 100 posts!!! I feel like I am part of the wdwmagic family now! :sohappy::sohappy: