Where is the kleenex to put the flakes into, just let em fall into the tatami?
Lol the whole danger thing is western bullshit. If anything it is riskier to do it yourself by pushing the crap deeper into the ear canal. Also most asians have flaky wax, mostly skin flakes vs that wet goop westerners get. So you need to see where that pesky flake is that keeps wiggling about in your ear!
As for cleaning if you belive doctors you shouldnt clean your ears, ever. Seen much nasty crap here in then states when it comes to ears.
And no, most japanese my family included all share cleaning duties, we do not go to a shop for it. Though I have to say it should be a service as most people end up empacting it deeper in the ear or use bullshit things like ear candles.
As for culture I guess it is that whole skinship thing. Massages, back scratches, etc are all those relaxation comfort things others can provide. Maybe it is some conspiracy to train kids to get married as those are those things you do not get being single.
And yes in media it is a sexual or realationship trope, and it only is recognizable as such by the younger generations. Show something like this to my parents or grandparents and they wouldnt get it.