Tie-dyed short sleeve t-shirts? Roach clips? I’d say LSD missionaries.
Mormons.
They were never led to my door back when I had a large winged gargoyle on the front porch (very like thisone). Funny how that worked.
ISIS
: golf clap : 
Sure its possible. Its the Mormon modus operandi (two young men proselytizing, with the suit and hairdo, backpack and books and so on ) described.
Its way beyond balance of probabilities.