I agreed that there could be benefits but that the downside is that they know when and where you go to church, or the grocery, or where you get your hair done, or even when you go on vacation. Her eyes lit up and I she replied that she would have to think about that a bit.
I'm not saying that I changed her mind, but that bringing the consequences down to something she could understand was much better than yelling from the rooftops. Mentioning church is especially impactful with a lot of older folks.
Good job talking to your community. The first step is that people are aware of the cameras - for my neighbors, most did not know about them, and immediately found it creepy.