Because they like to use it against ppl for exmaple "Yo I know 900 people ill get you farmed till you reset bro"
Followers are not important because over 80% of those people you will probably rarely ever talk to. So it is very unimportant. Only people who are important are club members. people who used to be in clubs you were in the past can be important too .-. some, not all
What dan said, I prefer to keep my friend list low, epically in farm wars or system wars so no one who is hitting you knows if your on. Having followers means nothing. And most of them are players who would of seen you on campus, who followed you hoping to get lucky and next day quit the app