I asked this in an AMA this year and got a response from one of the founders:
I suggested the following as a reasonable solution to their concerns:
It could be that when someone shares a camera or shares the SD card, that you could do another pop-up confirmation like you do for Friendly faces and warn them about this, or suggest they format the SD card first. Worst case scenario, maybe forcing an SD card format could be an option to resolve the concern.