....says Luton is the fourth busiest for this type of movement in Europe, with 12,371 movements last year after Paris Le Bourget (24,412), Geneva Cointrin (17,824) and Nice Cote d'Azur (14,091).
Luton is not the only London gateway for such movements whereas these other cities have limited choice. I wonder if you added up LUT, FAB, STN, NHT, LCY, BIG, OXF you would see London is streets ahead...