Unfortunately, I had the icky experience of staying airside in Terminal C, EWR after an international flight finally cancelled at 2:30 am after numerous delays. There were multiple international flights cancelled that night so all of the nearby hotels were full. We stayed in the terminal, along with other unfortunate people, until the UC opened at 5:30. No concessions were open except for vending machines. There were enough people that I felt safe but avoided the bathrooms until the UC opened. Not a good experience!