Mods should be paid through official channels, for the same reason legislators should be (and are) paid. It's a lot easier to bribe someone who's desperate.
That applies to Lemmy, too, although I don't really know who'd pay them.
Legislators get paid really well but they still take "lobbying expenses" and "donations" in exchange for votes and bills. Getting rid of Citizens United and setting up a proper nonpartisan anti corruption enforcement agency is still absolutely necessary to prevent this from happening.