Not saying this is ethical (although selling WiFi for 12$ per hour isn’t either) but I wouldn’t go as far as calling this an attack.
Care to elaborate on this? WiFi on a plane isn’t any kind of thing people are dependent on to survive and satellites are pretty expensive. Airplane WiFi is entirely a luxury good.
Do you feel that charging $12 to watch a movie in a theatre is unethical as well? How about $150k for a Porsche?
Finally it’s just way too expensive at that price.