Everybody has their own style. Some of my friends clothes I think are horrible, but its their style and It's what they enjoy wearing. It's like getting to know someone without talking to them, you can make a small opinion of someone just by what their wearing.
Personality and how open/exposed they choose to be. Its a question like why do some people eat kraft mac 'n cheese and others the store brand? I think that it all depends on your taste and what you find visually appealing. Why does my grandpa wear skinny blue ties and my dad square bottom red ones? No reason other than they both think their style looks better. It all depends on the girl.
Probably just personal style. Just because they have the same build / height and same whether, doesn't mean they have to dress identical. I'm sure there are several men with a build similar to yours, but they have their own preferences in what to wear.