You make an interesting point.
I would suspect that a small percentage of people making ressies know specifically what room they want, and short of that I don't see how the system (especially the
DVC system) could keep track of general requests like a building, floor, view, etc.
I think (at least hope) you are right that rooms that are specifically requested have some flag that prevents an arbitrary issuing of the room to someone with no requests. Still, I believe, if that requested room is the last one available on a floor, building, or view requested by someone at the time of check-in, then it will be given to the person checking in.
If your point is correct though it behooves anyone checking in to have and state preferences. Otherwise they are likely getting the best of the leftovers.
Seems fair.... so members beware... and ready.