I can understand that feeling, but I think it may be more a matter of 'drums were a unit unto themselves' than 'band doesn't count the drummers.' In fact, most of my memories of pep rallies were the drum folks performing exclusive of the rest of the band. I'm not sure the snare drum guys (it was always guys on snare, though the drum major my senior year was a girl) would have been insulted by not being counted as band members so much as 'Well, yeah. We're drums.'
Not saying it's always that way, but I can see where Carl-E is coming from.