Is Trick-or-Treating Dangerous?

It's about an article in TIME magazine.
They say trick-or-treating can be dangerous.
The parental fear of it first appeared in around 1964, when a woman handed out dog biscuits, steel-wool pads, and aunt poison to teenagers she thought too old to be trick-or-treating.
There have been reports of people with twisted minds putting razor blades and poison in taffy apples and candies. At least we have some risks when we allow them to trick-or-treating.

The day before yesterday was Halloween.
Kids who live in my neighborhood were doing trick-or-treating wearing cute costumes.
They visited the room of a couple who lives next door. So I was worried if they also come to my room, since I don't keep any sweets in my house recently. I was very relieved when they passed.
It seems like that Halloween is getting popular in Okinawa. When I was a kid, which is only about 10 years ago, there were no kids who wear costumes and doing trick-or-treating. Now I saw several kids who were doing trick-or-treating near my house.