I get asked this question by everyone I meet who doesn't read my comics. Especially businessmen I go on dates with. Which is strange, considering I also don't know how they make money. What even is business? Is it magic, are they alchemists who have learned to turn lead into gold? Probably.
Of course the truth is, I don't know who gives me my money-- once a month I check my mailbox and it has mysteriously been filled with gold dubloons. I think that's how all cartoonists get their money but I've heard some get different types of coins or tradeable goods rather than dubloons.