I think Disney is very very overwhelming for first-timers. Even if you've done your homework, you're never really ready for it when you get there. Not to mention that the advice you DO get prior to visiting isn't always helpful.
Imagine this scenario ... you've been kind of lurking around the various Disney boards, trying to get hints on your very first Disney vacation. You haven't read every single thread, but you're hoping to avoid all the trouble spots. Plus you've been asking friends and family who have been before what to be aware of, what to look out for, what to "know before you go." And everywhere you read, you see people complaining about line-jumpers and people who "follow their own rules." And all your friends tell you to "hold your line" when people try to push past you. The one big pet peeve you read about over and over again is people trying to push past you in line to be first into the park or on a ride or whatever. In truth, there's not really a lot of this that happens, but to read the boards or talk to people, you'd think that every single person is out to take your place in line. (Or maybe your only prior reference is Six Flags or the fair, where line-jumpers are rampant.)
THEN, you get to the park super-early, like everyone told you, and you're standing in line at the turnstile that you've been directed to or the turnstile that has a CM there or whatever. And then, a minute before the park opens, someone else comes up and stands at the turnstile next to yours (a turnstile that would appear to be ONLY for those folks attending a princess breakfast). Is the guy line-jumping? Of course not. Is he trying to sneak in via a turnstile that is only supposed to be used by Princess Breakfast people? Well ... no. But if the only thing you're looking for on your vacation is line jumpers, and you're overwhelmed by the Disney experience already and you're doing your best to navigate your way through by following all the signs, then yes. That is how the situation is perceived.
Clearly the guy
inkkognito spoke with had no idea that the Princess Breakfast turnstile was okay for
inkkognito to use at that point. He was standing where he'd been told to stand and was on the lookout for line-jumpers. He was protecting his place in line and trying to "educate" you that you were in the wrong here. Once you realized where the guy was coming from, a better way to deal with this guy may have been -- as someone suggested upthread -- to engage him in conversation. Don't blow him off, because that's what line-jumpers do. Be friendly instead of dismissive and you'll get a lot farther.