I don't know about the Japanese figures, but want to note those figures for Manhattan are just the residential population. The "daytime" population that counts all the workers who come in is 5x that.
I agree, but it's worth noting that the density of after hours (as in 2 AM) food spots will usually be related to residential density and not commercial/office density. There will always be exceptions (e.g. the East Village) but I suspect they are the overwhelming minority.
