I recently read that, compared to the rest of Britain, karaoke caught on much quicker in Scotland and Ireland - "that's where they had the tradition of collective singing...and more of a tradition of the ballad," Simon Frith proffered in the article in the Guardian.
I can't dispute the statistics, but it's illogical to conclude from them that karaoke is the evolutionary successor to ballad and collective singing traditions, and that the relationship is causal. Besides, collective singing in the British Isles is not the preserve of only Scotland and Ireland. It's a trivial issue in the grand scheme of things, but I think that what the statistics are purported to reflect is spurious. Here are a few reasons....
Collective singing The Welsh are world famous as singers. And in both England and Wales - aside from the old traditions of ballads and work songs - there is singing in schools, church congregations, football crowds, rugby teams, working men's clubs, scouts, coaches, hen-nights, birthdays, Christmas carols, folk clubs, open-mics, and community choirs; there are thousands of applicants for TV talent contests, and uncounted millions of singers in bathrooms and cars. Has karaoke been tried and failed all over England and Wales?
Market forces The spread of karaoke has many influences. Unlike the kinds of singing mentioned above, karaoke is a commercial enterprise and hosted by another commercial enterprise - its spread surely depends more on market alternatives/competition and the economic vicissitudes of pubs than on any ballad or collective singing traditions. Pubs and karaoke alike have a social role, sure, but economics determine their birth and survival.
Demographics There are loads of Scottish and Irish people in England and Wales, and other people from other countries with rich song traditions - surely enough to get a bit of karaoke off the ground.
To make any attempt at explaining the regionality of karaoke we need more details about exactly who is singing and where - there may even be an inverse relationship between singing traditions and karaoke.
As for karaoke itself, the British Isles' style is quite different from that in Japan. I wrote about that here.
There are a few Japanese-style karaoke bars and boxes in London (one box, coincidentally, in Frith Street). The bars are small and tend to be expensive business account type places. Boxes, on the other hand are cheaper and open to everyone. They really are the next generation. Being dedicated venues, boxes are more of a commitment for owners than either karaoke bars or the machine-hire variety but if karaoke boxes were more widespread in the UK, the regional propensity-for-a-sing-song as measured by karaoke uptake would probably look very different.