Good suggestion. My nose would thank you very much. Festi-boogers are interesting to look at but I would prefer to do without them.
My suggestion is...Tarps. Throw them down in the aisles/dance area. We have them everywhere else anyway already, right? Maybe some orange ones to denote the aisles. Long rolls of tarp could be put down the aisles every morning right after tarp run to keep the walking dust down the remainder of the day and rolled back up at night.
I felt like I woke up every morning with a smoker's hack. Well, actually I DID wake up every morning with a smoker's hack but that is beside the point. The air quality was horrific. I've got allergies and asthma and so the whole festival was a sneeze fest for me.
Why not just use good old fashion water? They were wetting some areas down with fire hoses. How hard can that job be to extend that to the pathways? That or use some sort of portable water wagon. Mud is BIG fun to dance in and doesn't choke up your lungs - well unless you face plant in it, but that's another story.