One was in a retail shop like 100m from our office, one of my colleagues actually went there to warn the personel, and it was taken down in the next minutes (I think they cut off the power of the cameras until necessary action was taken).
An other one was in a restaurant, right above the cashier and (most importantly) the credit card terminal. The name of the restaurant was visible on a floor mat, so I could find very easily the website and the e-mail address to send an e-mail to. But then I struggled when writing the e-mail. I didn't want to sound like a hacker (and was afraid to be prosecuted), but also I really wanted them to take it down, by citing some laws here in France that is very strict about video surveillance on the workplace.
In the end I didn't send any email. I'm not a lawyer, and there was too much risk IMO. Maybe I'll try going through the ISP next time I browse the cameras.
It'd be ironic if they threw more resources at finding the "hacker" than at securing their network...
It's to be also noted that you live in a country, where ISPs understood what you were telling, understood its urgency, communicated properly with the affected party and remedied it within hours.
There are countries where, in order to talk to a person who understands there is a public facing IP camera it will take extraordinary effort at best and at worst you will be termed 'hacker' for visiting the 'Insecam' website and police will knock on your door within next couple of months to a year; Now good luck finding someone in the police who will listen to you and actually understands it.
After looking up the ip address, I notified the ISP which in turn notified the customer and the camera was taken offline within hours.
While it may not be unexpected to us that such insecure cameras are sold, less tech-savvy users simply don't know about the risks.