Okay I am the Guild Master on my lvl 25 guild with my warrior however I only play my priest anymore. When I logged on to play my warrior for some casual play I noticed I couldn't use my mobile banking perk on my warrior (THE GUILD MASTER) because my reputation wasn't high enough.... I BUILT THE GUILD WITH THIS TOON AND FORGED EVERYTHING FROM RANKS TO THE GUILD BANK TO PLANNED RAIDS?!? HOW IN THE HELL IS THE LEADER OF THIS GUILD NOT THE MAX REP!?!?!
Apparently you didn't contribute much to the guild via xp otherwise you would be exalted. Seriously since 5.0 you can get exalted in a day without even trying.