There is a need. With long travel bikes an air shock can overheat on long descents. With certain types of suspension air shocks will blow through the travel very easily. Coils are better on drop offs and square edge hits and just about everything else. For general xc/trail riding air shocks are fine, but not when things get narly like on a DH course...which AM bikes are meant to be able to ride; hence 'All Mountain'. I'll quite happily sacrifice a bit of weight for an all round better shock. 




