Yes, but while circumgalactic orbit exists, it is far from stable. For example, check out the Spiral pattern rotation period:
http://en.wikipedia.org/wiki/Density_wave_theory
A rogue planet would be far more at the mercy of any number of forces than would a solar system of a star. And even a slight vector would over the course of a billion years result in a very unstable body.
Why wouldn’t more of them simply form like a star with star having the same orbital mechanics, while rogue planets ejectide from a planetary system would tend to be captured elsewhere or escape out of the galactic plane and into intergalactic space?