It comes down more to interpretation of the rules. Making snow-golems around people could be considered harassment, which is already a rule. saying FUUUU is generally the same as saying the actual word, since what you have said puts the word you are trying to say in our head. I could give some more examples on that, but it'd obviously not look good on the forums
I don't know what you mean by the multi-accounts thing. Generally though, the goal of a ban is to ban a player, and not their "account". So if you got banned and used another account to gain access to kreatious, I can understand the banning for multi-accounts. If you got banned just for having 2 accounts, that's a little hypocritical.
I would suggest playing by the golden rule (treat others how you would want to be treated), and generally being a good person (no swearing, etc.).