Well...I'm not a nazi. But at one point my fursona was a nazi fur but I don't usually go around telling everyone unless I'm asked to.
I don't hate large groups of people or anything. I'm only a fan of the German weapons, language, uniform, WWII history, and even Nazi art from that period. Once I started watching WWII movies, the sheer epicness of nazis running around dodging Allied bombs and bullets while yelling crazy stuff was kind of appealing to me. At one point a few years ago, Spike started out as a Nazi. He was a member of the Wehrmacht (not SS) and carried around an MG42 (despite its large size and weight).
*shrug*
I'm very much aware of who the Nazis were and the shame they brought upon Germany. The way I see it, that's not an excuse to not be allowed to have a Nazi fursona. I don't follow their ideologies. I follow their methods of intense fighting and gunplay.
A Nazi fur can be described as someone like me who's just a fan or they can even be real nazis. I've met my fair share real nazis. It's kinda obvious why their fursona is a Nazi. For the rest of us, we're just fans.