The idea is to make their diabolical ideology appear as benign as possible, which leads them to the most milquetoast of all possible sartorial choices.
Because “Brownshirts” is too obvious. “Blackshirts” won’t work in the U.S. any more because… Well, let’s just say that the Goths and punk rockers would take that badly. I think that there were “Silvershirts” and “Greenshirts”, too, so all that’s left is… Preppie-looks.
Yes, let them look like armies of WASPS (the extra ‘s’ stands for ‘straight’) because nothing intimidates everyone else like the image of cocaine-addled plutocratic college students from the 1980s…
Related: Tucker freaking out about the idea that tacos are considered Mexican food, screaming that they were invented in San Diego and are “American food! Mine! Mine!!”