Oh yes, I don't mean that's specific to Patreon the platform. It's just that in my limited experience dealing with a not that popular opensource software and dealing with support for an old school shareware back when that was a thing, the most entitled, the least friendly and the most aggressive emails were all from people who didn't donate, didn't pay or didn't contribute to the code (in the case of my opensource project).

And once you help them, they're not necessarily going to donate either or try to help in any way (a big percentage of those problematic users have the mentality of not paying for software ever). So filtering support to only supporters is a good way to stay sane as a developer and stop dealing with negativity.