The point is that if 11 random people accept the one nazi, then there are a dozen nazis. Because nazism is so extreme that it is only accepted by other nazis.
But also, that “1 nazi” is how it starts. Ever wonder how a bar becomes a nazi bar? It’s because one dude with nazi tattoos came in, was nice and quiet, and didn’t get kicked out even though he was obviously a nazi. And then eventually, he started bringing his buddies. And they were nice too. They were polite, they were orderly, and they tipped well. They didn’t get kicked out.
But eventually, the nazis outnumber the non-nazis, and that’s when things begin to devolve. Suddenly, they’re not so accepting. You start hearing drunken slurs when they think you’re out of earshot. There’s suddenly an undertone of violence which wasn’t present before. The regular patrons don’t feel safe coming to your bar anymore. Eventually, if you fit the demographic, they begin treating you like you’re a nazi too. And now the nazis have found their new favorite bar to hang out at. You as the bartender are afraid to kick them out, because you feel like you’ll be in danger if you do. And it all started because one nazi was polite, and you didn’t kick him out for not making a fuss.