I know a couple of the local restaurant owners and managers thru various benefit functions. A number of them are requesting a CC number for a Saturday night reservations. They do it as a result of the increasing number of no-shows. From their side, it makes it very difficult to plan menus and food volume and is simply not fair to the staff who rely on tips. They make their policy known when taking the reservation. Most ask for a cancellation by 4PM and give about a 20 minute grace period (w/o phone call) before they consider it a no-show and charge. I can't blame them and I cannot blame Disney for going this route.
I think this would be the reason for Disney having a cancellation policy. To make it easier to plan. I'm not sure of their current booking policies right now, but if they over book a restaurant fully expecting no-shows, but everyone comes it makes for very long waits for their guests. Or they could be fully booked and have walk-ups who they turn away thinking they really won't have room for them, but then a bunch of parties don't show up and they really could have allowed those walkups to dine.
I would think the potential $10 charge would be to encourage people to actually cancel a reservation they may have and don't use. Even if it was at your dining time. Say a notice comes across the check-in podiums screen at 5:50 that a 6:00reservation was cancelled. A walkup comes up wanting to eat, they can now say "Yes, we have a spot!" Where as now, there is no reason for someone to actually pickup the phone and cancel, so that 6:00 spot needs to be held because, maybe that party is just running late. KWIM???
Also, you don't have to call in a cancellation, you can walk up to the nearest full service restaurant and they can cancel any place for you. Or you can go to guest services in the park. They can all book reservations for you too.
I know others are not as courteous, but I don't think Disney will penalize you for even one hour late. I bet the late charge would not be given until the end of the day or when the meal time changes (breakfast, lunch, dinner), so if had one for breakfast, it would not be charged until the dinner time. This way they give you time to make it or cancel. It already sounds crazy.
This was along the lines I was thinking.
The current wording under Liberty Tree Tavern is "a cancellation policy applies and
may result in charges if you cancel with insufficient notice. Specific policies related to this facility will be detailed at time of reservation booking." I'm assuming the others restuarants are similar. I think this wording allows for certain policies to be in effect for specific times of year and/or days.
It could also be that they are putting out information on future policy, so when it actually goes into effect, people can't say they were blind sided.