I'm certainly not averse to taking my son to see princesses and was always very much about non-gender specific, no stereotype child rearing ... My son, though, had other ideas. I think pretty much from the womb he was "all boy," in every stereotypical trucks-cars-trains-roughhousing sense.
In fact, when he was four, he told me: "Mommy, remember how you said some boys marry girls and some boys marry boys? Well, I'm going to marry a boy because girls are just so boring."
Don't think he quite believed me when I said that the very fact he felt that way probably meant he'd someday want to marry a girl after all but, you know, mommy was OK either way. (Though I have told him, regardless, if he waits until he's 50, like his father did, to give me grandchildren, I'll be disappointed.)
Anywho, if I told him we were going to see pretty princesses in beautiful dresses he'd roll his eyes and say "Boo-ring" (lesson: be careful what you laugh at, because it sticks), but I thought I may just get away with it if I say we are going to see "Disney characters." And he HAS enjoyed the so-called "princess" movies he's seen:
Cinderella, Mulan, Sleeping Beauty, Tangled, etc. (I don't really think anything about the movies themselves are girl-centric and, apparently, neither does he, though he doesn't ask to watch them over and over again like he does, say,
Cars.)
Of course, if we walk into the restaurant and he's the only (or almost only) little boy, we might very well have a mutiny on our hands if he instantly dubs this a "girls' restaurant." Though I will say we ate in the castle at DisneyWorld last year, but that was with two girls (my friend's daughters) and my son was very excited (and a little obsessed, actually) to be able to "go inside" the castle.