It bugs me when they say anything that's negative. I don't mind, "These strawberries sure look good," or, "I love these things," but other types of comments make me uncomfortable.
One time I had to go to CVS to buy pin worm medicine. Pin worms are worms that are in a very private part of your body. (They come out in your bowel movements.) One of my young sons had them, and I treated his naturally with garlic (don't ask what I did with it). The instructions for pin worm treatment said you should treat everyone in the family. I was sure I didn't have them, plus I was pregnant and didn't want to take unneeded treatments, but DH decided to treat himself, and he didn't feel like getting intimate with garlic, so I bought him the regular (oral) medicine.
Well, when I handed the medicine, which was called Anti-Pin Worm Medicine, to the cashier, she said, "What are those?" I was fumbling in my purse and just acted like I hadn't heard her. Then she said, "Well, I never heard of those things." I just ignored her. I know that's rude, but I didn't want to discuss what type of creatures my husband may or may not have in his digestive tract. And no, she couldn't have been commenting on anything else because it was the only thing I bought. Very inappropriate. It's probably a good idea to just never comment on medicines.