> Himal Gautam, the director of Nepal’s tourism department, which is responsible for regulating expeditions on the nation’s mountains, said in an interview that using the gas was “against climbing ethics,” […]

Okay, but then be consistent and also ban bottled oxygen and the services of Sherpas.

> […] and that it would hurt the country’s tourism industry and the Sherpas who help climbers by reducing their time on the mountain.

Ah, okay, there's the real reason. "Climbing ethics" my ass.