I consider myself support for the only reason - DRG and his buff, SMN and his virus, NIN and his Goad and Trick attacks are all kinda replacable, while you always (or almost always XD) need 1 BRD or MCH in progress party.

I don't mind being the lower DPS in exchange for always having a slot in raid party. The only thing I mind are people who expect BRD to do the same damage as other DPS jobs (clearly not talking about A2 Savage here or Ninjas).