Sounds like a community event like Chico's Kite Day. Always a lot of trash left behind here to, I can say it isn't left by the serious local kite flyers but the families who come out to enjoy the day with others in the community.
I can't remember the last time I left a broken $300 kite in a tree or on the ground or a $60 lineset laying around.
Sounds like somebody was upset there were people in their park, did a quick Internet search to find dirt on kite flyers and found an article on India's Makar Sankranti celebrated January 15th or Pakistans Basant also celebrated at this time and read about the dangers of cutting line so used that to prove the point and keep people out of their park.
