> One rationale was that being drunk excused someone who spoke their mind That's not why they do (did?) it, it is used to force management and employers to soc

> One rationale was that being drunk excused someone who spoke their mind That's not why they do (did?) it, it is used to force management and employers to socialize, they have a very rigid social hierarchy and don't socialize much spontaneously, so they force themselves to do it. It's the same reason why they have a lot of national holidays based on nature or events (Keirō no hi respect for the aged day, Kodomo no Hi childern's day, Tennō Tanjōbi the emperor birthday, the green day, the mountain day, the marine day etc. etc.) to force them to take a break from work.