Despite multiple warnings, multiple people were caught recording (or attempting to record) video in both the HMV room and the standard Hentai room. A three-strikes policy was in place, and the third strike resulted in the events ending early.
I know recordings are something being discussed, but no good solution has been found.
Speaking un-authoratitively to the suggestions by IceFist66:
1. This isn't feasible for many reasons, including liability, security and management/supervision of the items.
2. That is what we did, and it still happened. Some people don't pay attention, some don't care, and some are just trolls.
3. This is what we tried to do, but at some point we as staff can't spend the entire event trying to manage the crowd. At first we kicked the person out, then we evacuated the rooms and forced everyone to come in, and the third time we shut down all of the Hentai events.
To be clear, there are steps that are taken when someone is discovered recording video, but frankly those don't really impact people who don't pay attention, don't care or are trolls.
Believe me, this is something that has been discussed and is still being discussed. It isn't an easy problem to solve due to the common and miniaturized nature of recording devices in society. I found someone recording during midnight madness, and when confronted they didn't think anything was wrong but they stopped and deleted it from their phone. Unfortunately, society is changing where many (and I mean more than a majority) don't see anything wrong with recording anything they want to any place they consider to be "public" even though FanimeCon isn't strictly speaking public.