He doesn’t hate the women and workers at the parlor, just the idea of the parlor itself.
I don’t think that’s a very good line of reasoning. By that logic there’s also evidence that the guy merely hates shops that are open late, because both of these places where open late.
That’s not exactly what I’m saying. Just that if you can make a connection between him targeting women or Asians, you can make a connection with him targeting massage parlors. It’s not like he went and shot up a Chinese food restaurant or something. He went after a specific type of business.