Some people saw that they had affixed things to the inside of the craft. There is almost assuredly an inner liner that is not structural that these were attached to. Just like an airplane.

This is probably true, to be honest. I retract that part!

Yeah, wait, what? I also hadn't heard of that, but if true, that's seriously messed up.

this is the first I've heard of that but it would not surprise me one bit