Paparazzi or Predator?

A couple weeks ago, Brett and I were shopping at the Disney Store in the mall near our house. We had the girls in the stroller and were talking to each other about possible gift ideas for our niece. A lady comes up to us holding a camera, a small point and shoot. She asks me if it would be okay to take some photos of the girls. Huh? Seriously?!?! I just looked at her like she was insane and said, umm, no. She said okay and walked away. WTH?!?! What was that about? Now, I happen to know that my girls are little cutie patooties but what did she expect my answer to be? What would be her reasons for asking such a question? I hate that I feel this way, but my mind always goes to the worst possible answer. I told Brett we just had to leave because I felt so uncomfortable, like she was lurking around every corner trying to take a secret picture of the girls.