I'm a hobbyist photographer by nature. Most of the times I use my 70-300 mm sigma which offers decent telephoto range for street photography and candid work on my DX Nikon D5300.
Street Photography for me is about capturing regular moments and depicting them in a natural way. I try not to interrupt the person being captured as the element of being 'Natural' is somehow compromised.
However there are times when a small interaction with some unknown person calls for a shutter click. They have a story to relate. So, I keep my words in accordance with the way I'd take the picture.