Manga Cafe in Bricklane

You can visit the Manga cafe in Bricklane which opened last year. not like the ones in Japan, the one in England has the cafe underground and art gallery and Sushi bar on the ground floor. Moreover the interior is more fashionable. Including free drink, the prices are:

1 hour - ￡4
3 hours - ￡9
5 hours - ￡15

I've looked for an average salary in England which was£23,024≒\470,000（!?!?）
I guess it was not a suitable number to compare...In Japan you can stay over night by ￡7.

I was wondering why Manga cafes don't spread just like in Japan? The main reason is probably due to the difference of the structure of cities as well as the lifestyle. Japanese people tend to use these places to spend over night after missing all the transportation to return home at night. Moreover, we simply love Mangas to start with (though I personally don't like them).
On the otherhand in England, buses are available from early morning and not many people wonder around at night. I wanted to check the financial data from Manga cafes in Japan, but they don't seem to announce such information.

Will Manga cafes bear the trend of free contents due to the spread of internet? I don't think these cafes will popularize outside Japan. I guess it only works in high population density areas.