It's not the fault of the bar. It's the background. Diffusion. You see, there is a yellowish-white background associated with this image. The brain sees this and thinks it is looking at a white background being hit by yellow light. It overcompensates this "artificial yellow light" by subtracting yellow from all foreground subjects. You've heard of the color formula yellow + blue = green. Now, this statement doubles as the expression green - yellow = blue. In conclusion, the reason green appears blue in this image is that the yellow background meddles with the whole color scheme.
