Actually, there was a time when GA was loaded too.
You mean he's not loaded right now?
In the show, he was booted out of the company because he was terrible at it. Then Ray Palmer bought it, so there's not even a company called Queen Consolidated anymore. He presumably still has money from something since he didn't have a job for ages and could still fund being Green Arrow. And he's now the mayor, so I imagine that's a decent salary.