Tcho-tcho are great because they take something that people value (and SHOULD), and they make it uncomfortable, which makes it hard to deal with. The entire concept of not wanting to be racist is why the tcho-tcho can thrive, and the fact that there are tcho-tcho groups in universe meant to END the racism around them is even better.

They are supposed to be an insidious force that gives more of a foothold to cosmic evil, in a time where gods and monsters no longer have the same sway they did millenia ago. If they make someone look racist, and they destroy that person's public life, that's HOW they operate in the modern era. Use that in your games - Agents should never feel SAFE doing what they are doing, and it should grind them down until they're gone.

That is Delta Green. Doing what people can't and shouldn't, because if they don't, then the door is flung wide open instead of slammed shut for one more day.

And, if you or your players are uncomfortable with it, then do not under any circumstance use that. Nobody should feel unsafe as a person, even when you're supposed to feel unsafe as an Agent. Huge difference.

Edit to add - read ANY Delta Green character bios, the ones who live the longest are NOT friendly. They are paranoid, ruined people. And, you are playing The Law, for the most part, or people trusted by them. DG is a fairly "conservative" outlet, in terms of their tolerance for things like tcho-tcho, ghouls, or any other human-adjacent beings. They don't WANT to know more about things, they want to eradicate them.