It would harm Stemmit and the community with it, if that would be the only possibility in Steemit's offer to make multiple accounts (and blogs with them of course).

I've learned that the harm is not serious, because you need to earn 10 times as much SP than your account creation fee. While you earn that, you give value to the Steem ecosystem. It's a give to get, seems fair to me. Therefore I don't discourage anyone to make more accounts for multiblogs until there is a better option.