Basically, I'd have to agree with Mentality about this. Ops can enforce rules however they want to. Preferably, they do it fairly, but whether or not it's fair, it's up to them. Unless other ops and/or the founder decides to prevent it, of course.
That said, I've never found Efnet to be particularly welcoming. I try to avoid it for the most part. The #mIRC channel can be helpful at times and at other times you can find people acting pretty bad in there. But like I said, that's not just #mIRC, but Efnet in general... and just my own personal experiences on that network. And that isn't to say that everyone is like that. There are a lot of helpful people there. Unfortunately, there also seems to be a disproportionate number of annoying/troublemaking people there as well. And then there's the issue where most channels on Efnet require users to figure out where their rules are in order to follow them rather than actually pointing the user to the correct location either with a topic or a message or something. That causes a lot of people, especially new users who don't know to even look for rules when there isn't anything in the channel that even references them, to be banned. And then there are rules that are, imo, rather stupid rules that aren't really useful and just harm those who don't know about them and are likely to break them without intending to do anything wrong. Yes, sometimes ops will warn you and then you're ok... other times they'll ban you outright without even telling you why you were banned. What I've found is that avoiding talking except when absolutely necessary in any channel on Efnet is the safest thing to do. And that's the *only* network where I feel that way... and I know a LOT of people who also avoid that network for the same reason. That should tell people something about how it's being run, but apparently those on it don't really care that much and that's fine. It all goes back to the original thing I said... ops can do what they want in their own channel, whether it's fair or not.