Squall didn't actually shake Billy's hand -- he didn't like doing it, it was A Thing -- but he did gave Billy a nod of acknowledgment. "Squall. I'm a SeeD from Balamb Garden."

He thought it was okay to give that much information out. People weren't always happy when they saw SeeDs, but they did generally respect them. "Who are you with?"

Or maybe a better question would have been 'where are you from?', only old habits died hard.