I posted the following on another thread. I thought it prudent to repeat it here:
As a Brit, I can prebook 14 days with the Ultimate Hopper. All 4 parks, both water parks for £252
I can get a day at Discovery Cove, plus 13 days at Seaworld, Busch Gardens and Aquatica for £111
Or... 14 days of Seaworld, Busch, Universal, IOA, Aquatica and Wet n Wild for £218
Plus various other combinations. I know what looks better value.
Speaking from a UK tourist point of view, most of my friends and colleagues I know now book a combo pass that includes WDW, Universal, IOA, Seaworld, Aquatica and Busch for around £445 for 14 days. They see that as best value, enough to see everything, and that means they now only visit Disney parks for half or less of their total trip. Other parks are eating into what used to be Disney days. And of the dozens of families I know (very unscientific I know) who are going to WDW, maybe two would even consider staying on property.
That's going to be a lot (again, a tiny sample) of off site guests not having access to FP+. And they have no plans of moving onsite just for the "pleasure" of shorter lines as opposed to inflated lines. It's I-Drive/192 or a villa in Davenport for everyone I know. They won't or can't pay a premium for staying on site. They don't see why they should.