It's cool, cause I'm in the military and can just walk across the street from where I work and pick one up for nothing.  But the biggest problem with gas masks is them fogging up and it's kind of hard to breath.
'...Smoking's bad, smoking killed my dad. Yeah, he was driving down the highway one day and as he was lighting his cigarette, it blew out the window. So he jumps out the door to save it, and ran himself over. Uh, you mind if I smoke?' -Olie Ollaussen, Ski Bum extraordinaire