laq, don't think many people with kids live that kind of lifestyle, even the ones in London (well unless they had a nanny).
I did a lot of it pre children and now mine are older ( one out completely, one at uni, one year 11) I do a lot more.
Lots of Londoners though preen over the "culture" but never really go.
When it comes it restaurants there just is a wider range of food from different cultures, near me we have Ethopian, Braziliian, Polish, Caribbean. Afghan, Phillipino and many more as well as your common/garden Chinese, Indian, Chicken, Pizza. This is not zone 1 either, so lets be honest when you compare the cullinary choice there is just simply more in London by nature of it being more diverse and much larger than any other city in the U.K. Lots of other cities are diverse yes, but not as many cultures/backgrounds as London has.
Also the writer of the article was trying to be funny I think, but as has been said on here before, the snotty attitude of many non-Londoners towards someone else's home is just as bad as the snotty attitude going out.
I'm originally from the North East, I love going back, but I can see why people are attracted London. The economic opportunities are greater, there is a lot more on offer in terms of entertainment. My sister's kids were desperate to get here having exhausted a lot of the opportuinities and things to do in Durham and Newcastle by the age of about 19.
There are arguments for staying out too, property is insanely expensive, its crowded, drinks are expensive and it can be very lonely, especially at the beginning.