Well, given how deep, breathy, and threatening the woman's voice is, I could imagine the kids thinking the audio sounded scary. Plus, they are reading the reactions of their mother who is clearly bothered by the audio.
I just can't believe people are outraged with the store over this. Like, what are they supposed to do? A customer got a hold of the PA. A customer. One of them. It's not like the company wanted to blast porn in their own store. And it's not like this is the only time it's happened.