You can roleplay as any regime under the sun and not adopt their views. Some gangs simply dress up, change their names and ranks, and do PK/turf Wars. Some go even farther by talking in German/Russian.

Implying that dressing up as a Nazi immediately means you feel strong disdain for people of Jewish origin is a pretty big leap.
Some people just like the aesthetic or the hierarchy of ranks, and I think that's alright.

Where I draw the line, and so should the rules, is when there is a hate filled discussion with either A. Racism, B. Offensive Language, or C. Harassment.