Sticky Fingers..............You Tell Me #1

Ok all of you, I know what's what, but I can't be there all the time when this or that happens, and you need to rely on your own savvy, which some of you, we all admit, have in short supply. But hey, I'll be a big shot and lend you a hand. Here's the question, you think what you should do with it, and I'll tell you whether you know how to act like you were raised right. (Now I'm not saying you weren't, please this isn't about your mother, it's about you, I keep my own rules, at least most of the time.) How do you advise the poor schmoe who asks me this:

Dear Madrone, I am in a pickle.My girlfriend's best friend's cousin has sticky fingers. I mean we can't go to the store, to a restaurant that something doesn't walk out with her that didn't walk in. Now I'm not a saint, and I have been known to stash the odd packet of Equal from the diner and who doesn't take conditioner and shampoo from the motel, even if you didn't open it, everyone knows they throw those out if you don't.But this one's a real prize, I've seen her lift an entire wardrobe, include matching underwear and co-ordinating press ons. No one says boo to her, her father is on the job. But this can't be right. Should I rat her out? Honestly concerned, Philly.