Response to Science Fiction, Double Feature Picture Show

In this article, the author talks of his/her experience of their sister's after party. It is Rocky Horror themed. The author also spoke of how the surrounding public viewed the people who dressed up as characters from the famous rock opera. It lead me to believe that there is an underlying inference that one can make about pop culture. That inference is that yes, it does define people of a certain time period or the niches that they take when watching something like Rocky Horror Picture Show or carrying out such other activities. However, could pop culture subtly be a means of conformity. I read what the author said about the opinions of the onlookers as they saw the Rocky Horror crowd. The general consensus was probably, "look at those freaks!" So i thought to myself, this was popular once and it was ok for people to dress up like this and act this out. So what happened? The same could be held for decades. Take the 70s for example, almost everybody wore the popular look of bell bottoms, yet you would be lucky to see a pair of bell bottoms on someone else than an aged guy afraid to let go. That is because there is a new pop culture and bell bottoms are just not part of it. So i want to know what is lost here as the pop culture changes, what exactly makes something popular, and why it is considered abnormal to think outside the pop culture box, and if popularity is based solely on what people like, then what changes so that people dont like it anymore.