I don't consider myself a bodybuilder at all. I'm a weight lifter, but I don't do it for the aesthetics of it - sure I post pics, but that's often just to gauge progress and also to help motivate myself and others of what is possible with good nutrition and effort.
I don't wear tight t-shirts or try and show off my physique, in fact I hate that. In the gym 99% of time I wear long trousers and a sweatshirt. Outdoors, I don't wear flattering clothes, but then again I'm not into fashion at all.
I don't particularly like looking at myself in the mirror anyway so I don't do it for that. I do it because I like being strong, I like being fit (I do fitness training as well), I like being able to lift and manipulate my bodyweight without any effort, and it's been genuinely helpful being powerful for playing rugby, helping friends move flats, and general day to day living is helped.
I don't know what reactions I get from other people in the street as I don't notice, I don't think I look big, in fact I think I look distinctively average. I don't really get fuss from people, but at the same time I don't look for fuss either.
Ultimately, some people like to be big, some don't, some women like big guys, some don't... there's no rule. I think in general if you're a healthy individual you stand more of a chance (that along with the possibility of a handsome face!

) - but it's also down to confidence and how you carry yourself. For a lot of people lifting weights and going to the gym helps boost confidence - that in itself has a greater effect on your own perception of life and yourself, as well as others, and how others perceive you.
I don't get drunkards or bouncers giving me looks or nods of "respect" or what have you. It doesn't bother me as I'm not doing it for the approval of others. I know that with my bare hands I can lift close to 600kg in different types of lift, and for me that's pretty cool. Then again to others, having an overclocked pc, and squeezing the best out of their system is equally cool - nowt wrong with that at all. Both require dedication and knowledge as well as time and practice and effort.
I guess what I'm driving at, is, people who know **** all about bodybuilding don't understand why you'd do it. Likewise people that know **** all about computers don't understand why you'd spend your time doing what you do to them. Ultimately it's a bit of ignorance as well as a preconceived erroneous ideas and stereotypes of such people.