I agree, I think this man uses a car, possibly both to pick up the anthrax (in NYC?) and to transport the anthrax letters to different mail drops or post offices.
Remember one of the men detained from North Olden Avenue in Hamilton, NJ? The one who had a car -- with Florida licence plates?
And more regarding the "Greendale School"/Franklin Park connection: Nabil Al-Marabh, described as "a lieutenant of Osama bin Laden," was just picked up in Parkdale, apparently a suburb of Toronto. Article posted here, "Toronto Cops swamped by terror leads -- 'Unbelievable activity' linked to Sept. 11 attacks."
Remember the Vassar expert, Don Foster, also believed the perpetrator may have had Canadian connections.
Muslim Students' Association of the United States and Canada
thought I'd share. :-)