One price difference I will confirm

While I have gone on record on several occasions noting that the price differences between the US and UK seem to get largely overblown, my exception to this rule is dining out. And yes, we have formal confirmation with numbers: dinner out in London, including drinks and tips, at $79 is double that for New York ($39). I hope that is taking into account the halved tip margin, unless I’m missing something 10% is still acceptable here while in the states it’s running ever closer to 20%. Note also that in my experience it’s the food itself that’s more expensive, not the adult beverages. So it begs the question, why are Londoners willing to dine out in the most expensive dining city on earth?