It wasn't like this when I lived elsewhere in Japan but every time I hang out with Japanese guys in Tokyo my age the conversation topic degenerates towards mizu shobai and prostitution.
At first I would look down at them for paying for company but eventually the big-city symptoms of loneliness, economic wealth and time-poverty start creeping up.
When you're paying 6-8k to spend your evening drinking with coworkers or more to treat kohai who probably don't want to be there it's easy to rationalize spending just a little more for a hostess or call girl with whom at least there'll be no pretenses. No one cares as the household bills are paid - economics trump anything resembling Christian morals
The only healthy escape I've found in this city is exercise and leaving it for the countryside at the weekends. The average Tokyo-roid seems pretty satisfied with the overall gender apartheid so who am I to try to change things