My parents would not let me join any groups, however when I was older, they really had no way of holding me back.
Looking back, I clearly understand why they would not be thrilled with the idea of me going collecting with groups on Purim,
Basically its an unsupervised group of teenagers, drunk and hungry for fun.
Boys that never smoked had their first puff. Others were overly drunk.
Some boys were talking and acting very inappropriately.
I cannot understand how the yeshivos or organizations permit this, they have an obligation that their students (especially if they are collecting for the yeshiva) to have some sort of supervision.
For those that really care about your children, keep them at home, make it as exciting as you can.