Hi Stash - People have asked over the years how many Montague residents use the airport -- most recently at the last Special Town Meeting (I think -- it was there or at one of the information sessions beforehand). It seems no one knows because nobody keeps track of that -- I think this time the Airport Manager said that it might be a dozen or so (maybe someone else remembers better).
Why are non-residents on the commission? You'll have to ask the Selectboard -- they appoint them. I know David Brule lives in Erving (the Millers Falls section, so he's kind of an honorary resident), and he's very involved in the Nolumbeka Project and the protection of Native American sites, so (to me) he seems like a good choice. But the Selectboard are the ones who really know.