Chris, I think you're reading slightly more into the comments here than is meant (or I'm going the other way!). Any concerns I have are that it can get you slightly tarred, even though there appears no clear reason to do that. The problem is that children are children and vulnerable, and young people are in a kind of limbo state where they are neither one thing nor the other, so best leave 'em alone and avoid the mines. This ain't the 40s nor the 50s. New rules; less open today, even in Europe.
Voyeurism is absolutely at the heart of street; it has to be, or why would anyone want to do it? It's really just a sort of urban hunting with a little thrill of getting caught, but probably not of being eaten or trampled to death. That's the single most obvious reason why people feel so disappointed when they discover some iconic photograph that they wish they'd made turns out to have been staged. She-it! Death of another dream.
The other good reason for doing street is that it sharpens your reflexes. (I bet few Leica M3 stars knew that; never mind, it wasn't that good.)
Personally, I'm a bit too chicken for it, and living in a tourist zone, don't find many visually interesting people to photograph. They mostly look alike, dress boringly badly, are lumpy, almost never beautiful and not what I want to sit in front of a monitor to play with. Were I in Rome, Milan, Paris, London, Cannes, New York, who knows. At least there would be hope! Even a plain woman but with bags of style is hugely interesting material. Men, I never find interesting. Artists and musos are excluded, though, as they have something else that can make them worthy of the trouble: possibly if they are already well-known, their aura rubs off onto your pics. And an impresive instrument (musical) aways lends glamour.