Doubt there is a loading issue on the front end of an A.C.E. 30.1, so airbags for overload is probably not the reason...
...But, there is a mentality that airbags on a leaf spring suspension can improve the ride on rough terrain/roads.
The idea is called airbag assist. It works similarly to Sumo Springs - by having the last several hundreds of pounds of load supported by the airbags as the bags are inflated and lift weight off the leaf springs.
-Since airbags are generally more compliant than leaf springs, the airbags are believed to absorb the lessor bumps in the road in a softer fashion compared to just leaf springs.
And, if the bag assemblies look like this, then it IS a significant suspension upgrade according to Kelderman:
Hope that helps.