I was in the lingerie department of my favorite department store, trying to find a bra that actually fits because I've gained a little weight. When I get to the counter with my purchase, this dialogue happens:
Clerk: This is a special sale bra. You can buy two, get one free.
Me: <mentally calculating my bank account> No, I don't think I want to buy two bras right now, let alone three.
Clerk: Oh, you're changing sizes, aren't you? That's understandable. When my daughter was pregnant--...
Me:

I don't think I heard anything after that. Certainly didn't say anything. At some point, I think she realized that I'm not pregnant, but I kept my mouth shut, my face an icy blank, and my wallet shut to any further purchases in the store that day.