Commies and Nazis (Fascists) are both extreme left, statists. They both give control to the government.
Laissez-faire capitalism would be extreme right, with little to no control given to the government.
It could be argued that a perfect socialist society also gives little to no control to the government, as it would technically be governed by the people.
Neither a perfect capitalist or socialist society exists, so we don't really have extreme right examples. Most "socialist" societies are closer to communist, leaning left. Most "capitalist" societies are still leaning right, aside from the regulations.
Putting fascists on the extreme right is the media's attempt to use a scary word (Nazi) to describe their enemies. The Soviets and the Nazis weren't all that different.