"It had not been prepared with a due sense of social responsibility to consumers and to society and was likely to cause serious or widespread offence."
Wicked Campers did not respond to the complaint, despite the authority contacting the company.
The complaints board expressed disappointment over Wicked Campers' continuous "refusal to engage with and respect the principles of self-regulation", the ASA decision read.
It also noted the difficulty around considering justification for the slogan, because of the company's lack of response.
Wicked Campers is owned by John Webb, a Queensland mechanic who started the company more than a decade ago.
Last year campgrounds including Abel Tasman's Kaiteriteri Beach Motor Camp and Piha Domain Camp turned away Wicked Campers because of their offensive slogans.
Wicked was last year dumped from the Department of Conservation's tourist information listing for those wanting to hire campervans.