I find that hard to believe. Women come in a stunning array of shapes and sizes, and there are much more obvious cues if someone is looking for them. The truth is that most people are pretty instinctive about gender, and getting past a quick assessment is much more helpful than worrying about every little detail. There's nothing wrong with exploring any kind of padding that appeals to you, but I wouldn't put much stock in hip/butt padding as The One Missing Element. Choosing clothing that flatters your shape is what most women do, and it works wonders.