My son recently received a gift from his employer. The gift was a Stella Artois beer dispenser. Well, this dispenser took small pony sized kegs. However, the dispenser did not have a CO2 tank. Instead it had an air compressor. Not knowing exactly how this elaborate setup worked, I could only assume the kegs had some sort of bladder that filled and forced the beer from the keg.
So, yeah, the idea is already in use. I think the upside is convenance. The user doesn’t have to worry about CO2. Just plug in the machine and pour a Stella!