I see that kind of resentment in every kind of recreational activity. Different people commit different amount of time and energy. This result in different groupings where those that commit a lot spend more time together and form clicks. When there are stakes involved those clicks will favor those inside the click and exclude/be hostile towards those outside.

Sport teams is a typical example but I also see it when the stakes are just how much a person can get out of an experience and how smooth the activity went.