For the friends who are "just to ashamed to[o] admit they like 'this kind of stuff'" you could always blackmail and/or play with just them - it's less embarrassing if everyone likes it I guess?
I get my non-RPG playing friends to play by introducing something cute and rules lite at parties normally *shrugs*
I get my non-RPG playing friends to play by introducing something cute and rules lite at parties normally *shrugs*