Warning someone is very possible. There is no need to be a moderator for it. How often have I warned someone at Wc3c before I became a moderator? Once, though that is not the point.
Being a moderator only gives more possible options, warning people so they don't go on a stray path is something that everyone is able to do, even though the official warnings can only be given by moderators. I'm not the type that gives a warning fast, but when I do, I do it once.
What Undead does has no particular meaning, or anything to discuss about.
As for the friends, being no friends. It is true what it said about it, but I don't think anyone will hang out with people who will force all that much. No alcohol or drugs is necessary to see how pushy those "friends" are. In my case it was something like: "Come on, take some Ed. Well, if you don't want to, you don't have to." But this question came back every two minutes