Watching the movie, I could actually justify that starting out as a cultural misunderstanding (Christmas in Japan is more of a date/party holiday, unless manga has been lying to me) that grew into an eccentric company tradition -- it was 6:00ish and the thing was nearly over when the Rickman Gang busted in. More unbelievable was a giant office complex with one security guard and no skeleton maintenance or security staff, geeks doing system stuff, or anybody camping out in their office to get some work done while it's quiet. Our building is 5 storeys, and I doubt it's been completely empty since the day it opened.