This is not right ---

Just as it is hard to keep up with new phrases, it is hard to know when rv.net posters are joking or not. In case the post wasn't a joke, free candy in this case is likely a term branded to someone perceived as a dirty old man. Think child molester with creepy rape van telling kids he has free candy. This is different from hard candy, which is when a child molester goes to prison and gets shanked. And most of today's hand signs have nothing to do with gang affiliation. Your part of the world may vary greatly!