Disney World Cracking Down on Selfie Sticks

On Friday, Disney World workers posted a "No Selfie Sticks" sign at the Magic Kingdom's Thunder Mountain Railroad.

Not only on that ride but a few others. They say they don't mind them if they are securely stored, which would make them unusable. I imagine people are trying to use them while the rides are going on, which I can only assume could be a huge hazard.