I think they ask ppl to bring stuff that's so out of the way so they can't have plausible deniability about showing up at wrong house:
"You're under arrest!"
"OH but I just knocked on the wrong door bc my car broke down and I needed a phone"
"But you brought along 27 brown M&Ms in a ziploc bag like the person you talked to online asked you to."
WTF is up with that - who other than a plumber brings a toilet plunger to a first meeting with any person?
I think they ask ppl to bring stuff that's so out of the way so they can't have plausible deniability about showing up at wrong house:
"You're under arrest!" "OH but I just knocked on the wrong door bc my car broke down and I needed a phone" "But you brought along 27 brown M&Ms in a ziploc bag like the person you talked to online asked you to."