Being a Patron (which is what Patreon was trying to do) traditionally meant supporting someone, no matter what their output. If your tortured genius put out one work a year, so be it. If they popped out Sunflowers then even better!
There doesn't have to be any quid pro quo at all.
It's what we now call Basic Income financed by someone's surplus.
Don't overthink it. It's not a tip, it's a gift, an expression of support. It may be something more, but in the end you're giving money to someone, period.
As an aside, it's really unclear if Patreon payments should be considered income in the US. It's a gift, but it's up to the giver to handle that. I doubt creators would need a 1099 in that case either.