There are many kinds of nudism - or naturism. There are people who just like doing stuff while not wearing clothes. And there are those who believe there are hygiene benefits. And people who link nudism with various utopian movements that break down barriers among people.
And there are people who believe in de-stigmatizing the parts of the human anatomy ordinarily covered by a bathing. The way this plays out in life, therefore, is that some naturists just want the chance to live in the raw in fairly private settings.