Hate groups are for haters. Why are they allowed to mingle among us? Why not stay in closets apart from society?

The First Amendment applies to everyone. 

The haters gonna hate in public or all that built up hate within will destroy them. 

i dont think they should be mingling among us either

What's the name of the one you run?

Hmmmm, not too sure your dream would have too positive an outcome. For an example, look to the origins of the Klu Klux Klan and its first 100 years. Secrecy of its members' identities was the hallmark of its foundations, yet its hatred-fueled violence reigned supreme. 
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