My feeling is that masks would cut transmission to others. As far as protecting the wearer, I've never gotten a good enough fit from an N-95 to cut heavy wood smoke enough to avoid respiratory problems. There is also the fact that after wearing it around a store, you'd have to be really careful taking it off or somehow sterilize it before using it again otherwise you might infect yourself with pathogens the mask picked up during its last use. That could be why CDC, etc, has been hesitant to recommend universal use. Having several masks or scarves would be ideal.