That's a good point, I had forgotten that there was text saying things would be "returned to inventory."
The notion of a penalty is an interesting one. If they gave you so many points to spend in selecting things, then a failure to claim one could result in a loss of points in the future, and then reset if you have a year where you claim everything. However I think penalties get problematic unless you have a reasonable period in which to decline things and if they don't give you an adequate amount of information about how much time you would need to commit to in order to claim something. There's also the issue of people not finding out times until the day before a signing, people who won things on days where they didn't have badges, etc.
You have a good point about providing an option to decline and maybe given enough time a supplemental draw can be done.
The trouble with the signings I found was the lack of information for the times they will happen when you are making the selection. If you have a conflict in your schedule you do not have the option to decline beforehand.
Proving an option to decline would be fair however there should be a system put in place to redistribute or have standbys. There was an assumption by one person I talked to at the WB booth that no one would pass up on their winning ticket - that was not the case it turns out.
It is a shame when fans are shut out of signings after a number of winners do not show up. That is a huge lost opportunity for a fan to meet the cast of their favorite series or an upcoming movie.
Buying an autographed poster afterwards is not the same IMO. Meeting the actors and creatives even if it is for a few minutes is great opportunity for those who are interested.