When users accept Moderator role on a stream, they agree to uphold the Imgflip Terms of Use. I don't have a screenshot of that popup, will look for it if it's important to you.
Stream Owners are allowed to adjust the Stream Rules for Spam, Foreign Language, a few other things. Stream Owners are not allowed to adjust for nudity, porn, harassment, maybe a few other things that are sitewide.
The provision for Spam adjustment is recent. MSMG is far more advanced on Owner/Moderator roles, rules and procedures than I_P. Y'all are in the stone age compared to that stream.