Two factors there: - Yes, sure the new 737 MAX is cheaper to fly per seat mile than the old 737 - In addition, in absolute terms a 737 MAX is cheaper to fly p

Two factors there: - Yes, sure the new 737 MAX is cheaper to fly per seat mile than the old 737 - In addition, in absolute terms a 737 MAX is cheaper to fly per _mile_ than a large 777 allowing them to fly small routes to secondary airports that would otherwise not be economical