In the case that LE catches Agora, everyone who ever accepted money from them from their referral system would be involved in organized crime.
This is a very different circumstance from when people where just buyers or sellers with SR1. If LE gets a copy of their servers, everyone they catch could share the same charges as the operators.
I think you're right. In the unlikely event they had the identity of people receiving the referral money I think they'd charge them too.
If they charged forum mods I think they would definitely charge you for that.
EDIT: spelling