For me, it's social dancing, specifically West Coast Swing. Because while there is just social dancing, and some who only do it, there's a bit of a culture of competition, and it has its own governing body for determining where you place in competitions, and when it does sound like a cult when described.
I think that’s a very self-important account of philosophy that lends the academic practices generally associated with philosophy far, far greater relevance and weight than they should be given. Philosophers like to think of themselves as being at the base of some hierarchy of truth, beyond even mathematicians. It’s nonsense.