My married male Japanese friends (all doctors or corporate high level businessmen) all work 6 days a week and work from 7am until 10pm. They do come home for dinner for an hour around 5 or 6pm, but then back to work for another 3 hours or to a businessman's social club. Add in commuting time, and they are only at home about 6 or 7 hours a day to sleep. They mainly spend family time on Sundays or on a holiday in the summer or around New Year's.
So it's okay they treat their wives like fuzzy slippers?