"Discreet" is now used by gay men who label and/or perceive themselves as "masculine", "tough", heteronormative, who don't think people realize they are gay at first sight.
The slogan "Be gay, do crime" is an anti-capitalistic and anti-authoritarian statement, implying that crime and incivility may be necessary to earn equal rights given the criminalization of homosexuality around the world and that the Stonewall uprising was a riot.