For me it’s the paranoia surrounding webcams. People outright refuse to own one and I understand, until they go on and on about how they’re being spied. Here’s the secret - unplug the damn thing when you think you won’t use it or haven’t used it in a while.
They, whoever it is, can’t really spy on you on something that’s already off and unplugged!
This is exactly what I do with my tobii eye tracker. I’m a bit paranoid about what it can see so I have it plugged into a USB hub with power buttons that I just disable when I’m not using it.