@kptfit Very good question. The answer is... absolutely. In several different ways.
Growing up, through high school and my first stint in college, I was very short and skinny. I have a young face (which I'm now reaping the benefits of), and I also sounded young. So, for most of my life, people first meeting me at a party or whatever always assumed I was someone's younger brother, or some genius kid that was moved ahead. Eventually people would get to know who I was, but it took deliberate effort on my part. I never dated in high school, and had very little game/action from 18-23.
Now, I guess the simplest way to put it is I'm treated as more of an adult by people I'm meeting for the first time. Looking healthy appears to demand more respect from people, and maintaining some level of fitness seems to convey that I have self-discipline. It's a double sided coin, though. Now instead of people thinking I'm a little boy, they think I'm a bro. Sure, I wear tank tops, but I also live and bike in Phoenix, AZ where it gets to 125 degrees in the summer. Of course people quickly realize when they talk to me that I'm not a bro, I'm just a socially-awkward geek in a fit body.
There's another side to this, too, which is how I treat other people. As one might imagine, I've done quite a bit better with the fairer sex in the past 6 years. I'm still awkward as hell, but I gained a LOT of confidence right away, and that confidence has helped alter my view of who I am, who other people are, and what's important to me. Of course, some of this is also going to be due to just growing older and wiser, but looking good helps.