As many have stated, there is an agglomeration of Buffalo Bills fans all over the globe.
I have traveled to many Caribbean islands, multiple European countries, obviously Mexico and Canada, Hawaii, California, Nevada, Michigan, Wisconsin, Illinois, Maryland, Texas, Arizona, Colorado, all over NY, PA, Ohio, Virginia, West Virginia, the Carolinas, Louisiana, Florida Keys, cruises, all-inclusive resorts, Minnesota, Vermont, Maine and D.C. always sporting a Bills cap or shirt.
I always meet Bills fans at airports or just casually walking the streets. Casually as in sticking out as a tourist. Trotting along so indifferently. Ok, maybe not so casual.