Personally, I started off with quite a fair bit of Street Shooting... primarily, it's free and no pressure from anyone.
What I gained out of street shooting are:
a) Good practice on operating my camera. I learned to change and check settings quickly on the fly. I've encountered opportunities where I saw a good composition or moments, but ended up with motion blur, poor DOF, wrong ISO etc... Those were lessons and experiences that help me a lot when I shoot events like weddings.
b) Trained my reaction and response. Moments on the street comes and go quickly. U get the shot, or u don't. I learned to compose shots quickly in my mind, and once the composition I have in mind presents itself, I raise my camera and shoot. Sounds simple, but it requires experience and knowledge of the focal length of lens I have and surrounding lightings etc. How does it help? Again, they were invaluable experiences for weddings and events I covered.
c) Practice on composition. We can't usually control the background or environment totally in street photography. Hence, composition on how tighly to frame the shot etc, becomes critical, cos' we don't want unwanted distractions in our shots. How does this help? When I started going for organised model shoots, I can further control the composition n frame my shots better.
There's also a great deal of things that I've yet to learn from organised portrait shooting... certain skills and considerations are not the same as street shooting, which some CSers have already pointed out...
Although there aren't many organised street shooting here, I do believe there r still photogs who roams in out streets...
Jus sharing my experience...
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