Originally Posted by hafizbat
But why would he have his shield in this scenario? I don't think he walks around the street with his shield on him right?
It was concept art, simply showing what a confrontation between Steve and Bucky might look like. There is no reason to assume that there will be a scene like that in the film, and thus no reason to over-analyze the artwork.
Also, in the still released today from the first day of filming, Evans has the shield slung over his shoulders like Steve often does in the comics, though he doesn't appear to be wearing the uniform.