This one last one is a grab bag just in case we do get some jerk that rules lawyers and delights in the "I'm not touching you" defense. Most people aren't going to have to worry about this one! Trust us! And we'll generally try to work things out as nicely as possible! But anyway: you can get banned for whatever reason and are not owed an explanation. In most cases you will get one, but that's absolutely out of courtesy, so if you've dealt a whole lot of bullshit, "fuck off" is maybe even more of a reason than you deserve.
Maybe you'll be asked to leave because you're not a good fit. In that case maybe it's nothing personal, maybe you're a good friend of Bob's that didn't mesh well with others. That doesn't mean you're a bad person and shouldn't be taken that way in the least. It just might be something as simple as, like, hoping you'd have more of an interesting and humorous personality than to just post Jontron reaction gifs for everything.