It's not uncommon - or unethical - for agents to have jobs aside from agenting. They operated strictly on commission, and standard rule of thumb for new agents is that it can take 5 years before they make enough to agent full-time. (Some less, some more, obviously.)
This is a scenario that should sound pretty familiar to writers.
Lots of quite good agents have part- or full-time jobs. You may just not know about all of them because they don't advertise it.
That said, I still think Cate's agent is bad news. But this ain't the reason.