Dude. Stop. The Bills and every NFL team not named Jaguars have millions of fans. Millions. In any group of millions there are going to be racists. There are probably also serial killers in there.
To say Bills fans, or specifically Allen fans, are more apt to be racist than others should be backed up with numbers; not anecdotes or pictures of someone's flag avatar. He has done nothing whatsoever to back that up because it is an out and out stupid premise and cannot be substantiated. That's why he has to go anecdotal.