I think this is the thing to remember, right here:
We don't mind paying because we want to support the dev, so he can continue to make Sync for Lemmy as awesome for Lemmy as Sync for Reddit was. (And let's not forget that it started out awesome enough to bring a lot of users to Lemmy as soon as it was released)
I've heard/read a lot of FOSS-or-die people donate to their favorite devs or apps or projects, so why is it so hard to believe that some of us are okay with donating to this? I paid to get rid of ads in Sync before I ever saw a single one - because I wanted to support LJ. Dude has done awesome work.