Personally, I don't think people in general should have any issues about body hair, clothes, makeup, or stretch marks. I know lots of people who do care, and I know lots of people who don't... Stretch marks just happen and I don't see why some people I know fuss about it. As you said, mothers definitely have them and people who loose or gain weight quickly. For me, I have stretch marks because I there was a point in my life that I grew a few inches over two months. I think people shouldn't conform to a silly social or cultural standard just because other people do... and if someone does care about them so much, I wouldn't bother talking to them anyway :p