You could try to apply for grants. 20K+ chats sounds like a large number -- you must live in a 1M+ person metro area, right? It would probably be fairly easy to get a four figure grant from one agency or another. You could frame it as "localization of generative ai to the regional culture of X", or as a tourism thing, etc.

You could also sell advertising the old-fashioned way -- ask local businesses or perhaps a local university if they'd like the model to mention them in certain prompts.

But your best bet is probably to treat this as a loss leader and put up a small banner offering "In-Person Generative AI Consulting" in your metro area.