Sleeping bag usage requires responsibility, intelligence and great physical dexterity. A wild dog is also handy. And maybe a disco ball, although I don't see how. Regardless, preparedness is the key to safe and proper sleeping bag use. You wouldn't believe the number of fucking camp-happy morons who just grab any sleeping bag whatsoever and casually toss their tender flesh and brittle skeleton inside, exposing their immensely mortal bodies to whatever cruel fate may lay waiting for them, be it a large metal spring trap with large metal knives shooting in every direction, or some huge Kodiak grizzly bear with 8-meter-long teeth and fur made of glass and nine heads and two very long tails and gills on his underside near the front legs and the wings. Or perhaps they'll be luckier and it will only be a bottomless pit, or it will just be filled with superglue, or how about honey, and nearby are a bunch of bees? Bet you didn't think of that one.
In any case, the exact problems encountered are not important. Well, they are, I suppose seeing how they'll kill you and painfully too. Imagine you got in a sleeping bag filled with red-hot lava! Or if you were wearing a new dress, and it was filled with bleach or something... woah.
Just think about it.