The Chinese phrase on the button, "没人牵手 我就揣兜", roughly translates to: "If no one holds my hands, I have to hide them in my pocket." In the context of romance, when you're single, you need to be independent and self-reliant. Perhaps the artist is playing off that theme, given China's value in the principle of self-reliance? I guess it's sort of a cute idea - using pigs as part of Mao Zedong's Cultural Revolution Military.
Communist artwork on display in a Beijing Hutong.