You're exact words were "snakes do not get loose on there own"
Snakes is plural, more than one.
And yes, snakes do get loose on their own. It's called escaping.
And this snake did not escape because if you read Tim's post, you would see that they let the snake roam the house.
I believe that the point he is making is, if it escaped an enclosure, then either the human did not latch said enclosure, or built it to poor standards. In turn, did not escape on its own.
Sheep, Wolves, and Sheepdogs
"Most of the people in our society are sheep. They are kind, gentle, productive creatures who can only hurt one another by accident."
"Then there are the wolves," the old war veteran said, "and the wolves feed on the sheep without mercy."
"Then there are sheepdogs," he went on, "and I'm a sheepdog. I live to protect the flock and confront the wolf."