I know segways can't turn unless you use a handle, but that still doesn't seem safe...
Which is to say I don't think I'd do it, or be around when someone else was doing it, but if they want to do it, have at it.
The first two pictures you provided were from Beijing around the time of the Olympics.
It provides a stable shooting platform on the move. Much more stable and less wobbly than the Mk 1 Upright Locomotive Appendages while walking, but at a running pace. The downside is that that advantage is lost on uneven surfaces.
As for the bomb squad guy, wouldn't you want to get away from that bomb as fast as possible?