From reading it, and from having read some PFSD comics back in the day, I can suggest this hypothesis:
He was born into wealth.
He has wealthy friends, which is partly just because you're in the right social circles and people like to be friends with others who are on the same socioeconomic level so disparity of wealth isn't a barrier.
He doesn't personally have wealth. This suggests his immediate family wasn't terribly wealthy, perhaps they experienced a decline around the time he was a lad.
He went to Dartmouth, with annual undergraduate tuition of $43k in the 2012-13 school year. A community college typically costs about $2.5k - $3.5k and an undergraduate program at a state school around $6k - $13k. From this we can infer that he had some financial assistance available beyond student loans (which he mentions working to pay off).
He takes / took antidepressants. This suggests a significant emotional and/or behavioral issue, but it could be overprotective parents wanting to throw a pill at their normal kid to make him stop causing problems. Because he continued taking them as an adult, we can be charitable and assume he needed them.
At some point he began to alienate from his social circle. Perhaps this was linked to his economic decline. He mentions people offering him loans, financial advice, networking, etc. Clearly there were still people who considered him a friend despite any alienation.
He seems concerned with authenticity. He also seems enamored with the idea that he can see through the bullshit of our society and few other people do. He considers that supposed talent / trait worthwhile.
I'm on the fence as to whether he considers himself a crusader for the poor, possibly counting himself among them, attempting to increase equality. Or whether he just doesn't want to deal with money and would like an option where he does things and lives and eats without participating in the rat race and checkbook balancing of "work for paycheck and pay money for rent and food."
His language is similar to that of Harold Skimpole of Dickens' Bleak House, a wastrel living off the goodwill of wealthy friends who consider his eccentricities charming. Yet Campbell clearly understands what money is worth, and that he can enter a 7-11 and exchange a dollar for a candy bar. The clerk won't accept just a dime for the candy bar, nor will he expect $750 for it.
He clearly doesn't want an economic relationship where he makes comics and people give him money, but if he doesn't make comics they don't give him money. He also doesn't want a relationship where someone hands him money and expects that he will hand them back a book. It sounds like he wants to be supported and be able to do whatever he wants with no expectations placed upon him.
This is different from patronage, which would be one way of getting what he wants, because patrons tend to expect you to produce something. The patronage relationship is somewhat similar to a gift economy, wherein the most powerful person is the one able to give the best gifts, and where accepting gifts beyond what you can return lowers your social standing. The patronized artist is kept alive and working, but it is known that he is supported by the patron. The works of the artist are in some way aggrandizing for the patron, and that detracts somewhat from the prestige of the artist. A meager artist won't add much prestige to the patron, so he cannot get a patronage, although he actually gains prestige from being associated with the patron in addition to the income. And a strong artist will lose much more prestige than the patron would gain, so the patron courts him, but the artist will try to be self-sufficient if he possibly can.
Anyway, despite his meandering talk of money being pointless and how human relationships are what matter, I 100% doubt that Campbell would enter into a true patronage relationship because it would quash his ego. He believes at this point that he's a strong artist.
So, as he says, it will be interesting to see what happens. His landlord can surely kick him out, but if his landlord is a real shitter maybe he has Campbell's stuff thrown out into the street and beat the shit out of him if he fights back. That's how the real world works.
People with their heads in the clouds get stubbed toes.