Every collective has a sense of appropriate and inappropriate practices but this definition of what constitutes appropriate and inappropriate practices can be a tremendous source of unfreedom.
Just ask the lesbians, gays, bisexuals and transgenders. In almost all societies, they are regarded as engaging in inappropriate practices because they do not fall into the socially acceptable categories of male or female. Just ask the gays who were beaten up by their fathers and brothers and were told "magpakalalaki ka". Just ask the lesbians (like the contestant on Philippine Idol) or gays who are told by society that looking like a man or a woman is inappropriate (some collectives, for example, still insist that women should not wear pants).
Even "straight" men and women have to live with an unspoken code of what constitutes appropriate and inappropriate behavior. Men, in general, have to live by a standard of what it is "to be a man" which includes a certain deportment (avoidance of effeminate gestures, for example), corporealization (low voice, for example) and certian practices (not crying, for example).
Societies cannot live without a sense of appropriate and inappropriate practices but forgetting that things need not be the way they are can lead to grave injustices. Hitler and his Nazi party, for example, promoted the ideology that the Aryan race was a pure race and this was used to justify the extermination of many other races to prevent contamination. What Hitler did was extreme, yes, but the point is that we need to re-examine our sense of what constitutes appropriate and inappropriate behavior once in a while to prevent ourselves from perpetuating less visible injustices.
To a large extent, the women's movement best exemplifies this attempt to question practices and to expose the marginalization and subjugation of women through practices that have no logic beyond that the fact that practices that reinforce the subordinate position of women are a part of our collective culture and history. For sure there are other areas where practices (and representations) are a source of injustice and unfreedom.