Warning: long-ass ramble follows.
TLDR: swastikas are wack, but they scare your teacher.
These guys and their SS symbols remind me of a story my uncle used to tell...when he was little (eight?) he would draw swastikas on stuff just to get a rise out of my grandmother. He didn't know what it meant; he just knew it made her mad.
Maybe these guys actually are white supremacists. It's possible that they know exactly what these hateful symbols mean. But also: skaters and punks are drawn to anything that pisses off mom and dad. Skulls, blood, knives, naked girls, satan... it's a very "sixth-grade boy-drawing-on-his-notebook-in-1986" sort of aesthetic. One that Powell has kept going a little too long. When you're ten, you think it lends a dark grandeur to your wooden toy pastime. Pay attention to me! I'm a scary little badass! So, swastikas and SS totenkopfs: the most forbidden of the forbidden. Guaranteed to get you kicked out of seventh period social studies. (And sent home, where you can skate.)
Except lately, real racists have figured out how to cynically play this both ways. Sell shirts to the study hall provocateurs while dog whistling to their actual-skinhead buddies. "Oh, look at the snowflakes flurry about when I wear a swastika tank top/replica afrika korps jacket/confederate flag bandanna/MAGA hat! Can't they take a joke?" (Psst! It's not a joke.)
According to their own shop info page, "surf nazis" (which later became "skate nazis") want the word "nazi" to mean "uncompromising." They want to use it as a synonym for "hardcore." But do you know what it makes me think of?
The Soup Nazi.
The Soup Nazi Seinfeld episode was about a very average fish who wanted to be the boss of a tiny, tiny pond. An extreme gatekeeper, uncompromising in his pettiness. Seinfeld got criticized because people said "nazi" was too strong a word/idea to put with "soup," and I get that. But in a way, all real nazis are soup nazis. Petty little people who think they ought to be in charge of the world. "No surf for you! No skate for you! No human rights for you!" Maybe part of the point of the Seinfeld episode was to decouple "Nazi" from the connotation "ruthless evil war machine" (which to a certain kind of junior high brain sounds badass and cool) and associate it with "rule-obsessed cafeteria line tyrant" (objectively not cool.)
But if we don't want to throw around the word "nazi," what word can describe that guy who thinks he's in charge of what tricks are illegal and who skates the spot?
For your consideration: "surf karen?"
Edit: although "Karen" is uncomfortably gendered. I guess from now on if I see "x+Nazi" I'll mentally find/replace all with "x+hall monitor." Even though it's too long.