Check out the /r/keto sidebar on Reddit. I keep various PDFs in Dropbox of keto options at various fast food establishments. You can always get taco bowls with no tortillas, McDonald's without the buns, a burger without the buns at a burger joint, etc.

For emergencies, I keep a few shaker bottles in my car with protein power already added. I just add water if we go somewhere with no keto options.