But there are still certain societal norms that take precedence over these desires for "self expression" and violations can be punishable under the law or local ordinances. For example, while wearing a Justin Bieber shirt shows lack of taste, wearing a "FU©K Justin Bieber" shirt can get you thrown out of school, fired from your cushy job at Subway, kicked out of Disney and potentially arrested for profanity.
Societal norms have evolved over the years (thank goodness - nobody wants to see me in knickers or pantaloons), but there is still a call for modesty at some level.
Taking the argument to the ridiculous, if we really want to address this, the most logical sense of the situation would be to require bathroom use based on the way we were all born. Which requires total nudity. None of us were born clothed. Nudists had it right all along. Those of you who have had the misfortune to have seen me in real life know that this would be the WORST POSSIBLE idea.