We went down recently and got the Magic Bands. Disney uses them in five ways:
1. Ticket into the park
2. "Fast pass+" for some rides in the park
3. Purchases (with a pin, if your card is tied in)
4. Room access if staying on resort.
5. Photo pass (photos shot by in park employees)
In most cases, these are actions that for >95% of us would be tied to our credit card transaction. Even the old paper fast passes would have been tied to your park ticket (which is probably tied to your credit card).
The photo pass is one that previously was not tied to your credit card in any way. You would take pictures and get a code, if you never bought the code or tied the code to your online disney account they would not have your picture. But I am sure Disney has plenty of CCD in place and could tie in your entering the park to a picture if they wanted.
I really doubt they are tracking people in the park. Their RFID sensors stink! You have to orient the band just right to get the RFID close to the sensor. You have to hold it still and sometimes swipe two or three times. I doubt they are long range scanning your RFID in the park without your knowledge.
Also, you only get three of the new fast pass+ "experiences" in the park each day. So they really will only see you in three spots. For them, this stuff is probably more useful for load leveling than privacy invasion.
BTW, problems with the system have been all over the place. Disney invested almost a billion in it and they were considering dropping it, but it worked pretty well for us.
So in summary, if you are skeevy about this at Disney World, pay cash or use gift cards to buy your tickets.
