one of the biggest advantages is size/ weight, air tools don't need their own motor and some [like die grinders] can't be matched by anything electric for size and manuverability, and in the case of sanders/grinders, electrics have lower rpm limits, speed = power
the fact that air tools don't have an electric motor makes a big difference in price as well, much cheaper to have a wide range of air tools than of individual electric ones to cover all the bases
electric impact wrench? electric paint sprayer? electric chisel? electric sand blaster?
the compressor doesn't need to be all that big, other than continuous DA or sand blasting use, just needs to be sized for the intended use, especially if you'll habitually have more than one person use
others may have different takes on it, but pneumatic is much more efficient
Bill
