Gardner actually wore a mask for awhile before his power battery blew up and he went nuts. Throughout the 80s and 90s he was a massive arrogant tool as a result. I believe he went by his given name to distance himself from jordan as well use the fist of the guardian uniform, as opposed to the standard issue one. He was also pervcieved as the subordinate GL, disite the fact that the only reason jordan was chosen over him was the fact that jordan was physically closer to Abin Sur's ship when it crashed. I believe stewart felt the same way, although the writers at the time felt compelled tomake him the steriotypical angry black man. But the whole mosaic storyline kinda gave him a reason to be pissed. He got a pretty crappy job given to him cleaning up the guardians mess.
That's how I saw it anyhow, gardner and stewart had to play secod class lantern to a guy whos personal life was in such a mess that he actually was icarcerated as a result of his alcoholism. (I think he killed a guy) gardner and stewart were like, "screw this, we're going to get some crediit. No way is this clown superior to us"