Filed alternatives are for fuel planning and satisfying the bureaucracy (showing the flight complies with ETOPS etc). In a real emergency the pilots will selec

Filed alternatives are for fuel planning and satisfying the bureaucracy (showing the flight complies with ETOPS etc). In a real emergency the pilots will select the most convenient airport based on whatever factors they are presented with. Especially so in today's world of paperless cockpits, in the past having the correct approaches to hand might have tipped the balance in favour of a planned alternative.