Most cameras are insecure by default. Check out: http://www.insecam.org/en/ or https://www.shodan.io/ The first isn't even using default access creds, which I suspect is what was 'discovered' in this case, but cameras that immediately hook up to the internet with 0 restrictions to access.

For the goal of recording a cat scratching their car or catching an imaginary thief neighbour (a magpie or fox stole that thing that one time, you dullard) people will plug into Chinese, Russian, and American video surveillance networks in no time and pay for it.