Yeah, too many salarymen get drunk after work. That explains that it's not an isolate case. Actually, if we include other Asian countries, it could be said that a big proportions of male Japanese tourists have of propensity for buying local girls or even do orgies. It happened a few times to me to ask a salarymen if they had been to this or that country in Asia. For example, I asked about Thailand. As the guy hadn't been there, I asked if he'd want to, but he replied that it was very dubious for a Japanese man to go alone to a country like Thailand, because so many people just go for sex. Before it becomes dubious for any man to travel alone to Thailand, Korea, the Philippines or China, there must be a good reason (and there is).