Nobody likes it when you take credit for somebody else's work. I'd know, what with me being the inventor of the glowing red "cancel" button on the side of the toaster (just trust me)... but in terms of having credit stolen from them, is there anyone out there more wronged than Abaraxx?
Probably Bill Finger.
Zongar was just your average wealthy socialite... actually, he probably wasn't, since he owned a magic amulet and his legal name was fucking Zongar. This amulet contained a green spirit named Abaraxx, who would assist Zongar in fighting crime... by doing all the fighting for him. Whenever Zongar was up against a wall - maybe the trail went cold, maybe he was captured, maybe he just couldn't open the door - Abaraxx would be summoned, they'd do all the work, and Zongar would get all the credit.
But every wish has its price. While Zongar achieved fame in the short-term amongst his piers, he couldn't sustain it outside his world... and by that I mean he probably wasn't very popular with readers since he only ever appeared in one issue.