I completely understand Disney's policy on excursion cancellations and won't complain about them. What I'm disappointed about though is from my understanding (and I could be completely wrong here) that even if an excursion is sold out online that some availability is still there for booking on arrival date. If this is true, it's not worth it for me to chance it and not book something in advance with the hope I'll get lucky when I arrive. Is this true, or is that just the case for reservations such as Remy & Palo and onboard activities?