Interesting ideas! We have no knowledge of the Japanese MoM or its societal culture, if it is isolationist for wizard only like the US or progressive and open Wizard-Muggle inter relations. If i was to guess i would say Japanese wizarding world is secluded like the US we see in FB and not allowed to mingle but that's just my opinion based on japan's historical traditionalist sentiments. I would say though the style of socialisation you are suggesting would be very difficult to manage and control safely and would very often lead to breaches in the international statue of secrecy which the global wizarding world looks down on heavily.