Ya know that Iron Mike (I think) hasn't taken off in Pittsburgh though some fans wear an I-beam on their heads ... a la cheeseheads. We take great pride in not having a mascot or cheerleaders. We just play football. 
I can see why they wouldn't have cheerleaders. You wouldn't be able to find enough hot chicks in Western Pennsylvania to field a decent squad.

But I always respected the real reason for them not having cheerleaders.