Also not a surprise because you could see it all leading up to that (the touch of a male, and the actions regarding the other women in the party). I do like the way it was revealed though, complaining about how calori... I mean exp goes to the breasts and makes the armor not fit. In that way, it's less of some "shock" attempt, usually found out when someone's armor is broken during battle or something in the standard shonen mangas, but as a gentle humor.
It's true that the MC does need to learn to rely on others (though it definitely doesn't help that the hero party doesn't think).