Yeah, mal nailed it. As someone who has been responsible for the hiring and firing in a small business (not related to food service, but the principle is the same), you don't actually think thoughts like "Oh, well, that guy's making X, and this guy's worth more than him, so I'll give him Y." I know it looks that way from the employee's point of view, but each employee makes their own deal with the company, and there isn't any relative evaluation or worth assessment going on.
You should talk to your boss. Don't complain about the new guy, just hold him to what he said about talking about your server training next week.
Are you at least bagging hot waitresses out of the deal?