Wikipedia is only a place where someone or groups of people have written what they believe or want to believe until someone or a group disagree.From Wikipedia:
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So they technically are Easter Eggers. However, that term is unsatisfying since from both marketing and personal viewpoint perspectives. I would not recommend "muttbars" since there are many negative connotations with the term "mutt".
There are many many examples in life where a slang meant to be negative is adopted by a group and becomes a name they are proud of. Marketers use this to their power.