This. I tried getting a pod of 4 (tried about 5 times), no dice. So I tried 2, and that worked. Tried getting another 2 (so whole family can go), no dice. So we have two. The problem with these "free" tickets is I'm willing to bet a good chunk of people just snatched them up in case they go. There will be a fair amount of people that got tickets that don't show.
IMO, it would have been better to just charge a nominal fee (like $5?) per seat and donate proceeds to charity. That keeps out the people that are just getting tickets "in case", and probably results in better attendance.