Most creators that make big bucks on Patreon do not use it for donations. They simply use it to sell stuff. Like https://www.patreon.com/PokeGo20 who have 62k "patreons" paying for a "fake my Pokemon Go position" software. Or https://www.patreon.com/chapotraphouse who make over $100k/month by selling access to their premium content.
Patreon is needed because selling on the net is such a hassle. Nobody wants to fiddle with their credit card unless it is important. Nobody wants to give it to "someone on the internet".
It's funny, because it would be so totally easy to create something like cash on the web. It just needs someone to start a business of selling tokens for $1.10 and buying them back from whoever comes first for $1. Voila - internet cash. Sell sealed tokens in stores (over the counter or via a machine that eats coins) - voila! anonymous internet cash.