Two times come to mind very quickly. Bought a wig at K-Mart years ago and I didn't like the way I looked in it when I got it home. Took it back and the return lady asked me very caustically and loudly, "Didn't it fit"? I felt very humiliated.
A few years later I went to Lane Bryant and looked at a dress. Didn't buy it at that time because of lack of funds. Went back the next week to buy. Quite a few people in line when I went to check out. One of the SAs came walking by and proclaimed very loudly that she had seen me looking at that dress last week and that I would be very happy with it. Everyone stared at me. I could've melted into the floor.