Sociologists would not consider fans of the rock musician Bruce
Springsteen to be a group as
They don't interact in any meaningful way.
Explanation:
It is important for a social group to have a meaningful interaction that is helpful for the people or integral to their life in some way that involves them in capacity and to create a culture.
The general fan of Bruce Springsteen would probably not care to meet another fan unless in a concert setting and would not form any deep relations whatsoever.
They do not interact in meaningful ways enough to justify being called a group thus.