Are you guys kidding? The boys at the bottom of the frame make it. Without them it becomes almost an abstract, and a much less human and much more ambiguous scene.
Their interest in something outside the frame adds a new element of the unknown, and their total indifference to the scene immediately behind them has a couple of effects, all good. We're pretty sure the figure in the fountain isn't dead, and hasn't fallen there -- we're quite sure now that the figure is digging around in the fountain, for reasons blessedly unknown. Their indifference also lends a frisson of the surreal to the image, another layer of 'what the hell, now? what?'
The boys set the scene as "probably a mall or something" rather than god knows where, where, without context, we have no notion of what the fountain could be, or why the figure could be in that position.
Street is, for me, about combining things we understand and know, a context in which we feel comfortable, with elements of mystery and narrative. Without the boys we lose most of those pieces, in this one.