The petition 'isn't getting much traction' because the Naked Bike Ride is (1) a well-publicised,harmless annual bike parade from which it is perfectly possible to protect your children, and (2) because the petition is comically badly written.
My sister did it in our home city, years ago, when she was in her late 20s or early 30s, wearing body paint and a gstring. She said it was endearingly goofy and fun.