Pantone 448 C is a colour in the Pantone colour system. Described as a drab dark brown and informally dubbed the "ugliest colour in the world", it was selected in 2012 as the colour for plain tobacco and cigarette packaging in Australia, after market researchers determined that it was the least attractive colour.
Pink is fun and light-hearted. And I don't think many smokers would have an issue with it if all the packs were the same color, because it wouldn't look like they chose the "girly color".