I wonder why they don't think that the Gujarati bros and sisters would like to visit with everyone else? Did they have a different language session or something? That is the only reason I could think they would try to segregate and even that is pretty lame as most people like meeting people from other places. I bet they took one look at the segregation and all went home. OTOH, ifthey are Indian natives, they proably went to the car park and ate their own lunches and made tea the way they like it on a burner.
Recent immigrant Indians are not likely to eat out unless required to and are likely to make tea the way they like it. I'm related to many- I know of what I speak.
I imagine you are in UK (tea reference) . If you get a chance, try Kashmiri tea at an Indian or Paki tea place. It's awesome!! Or Karak, which is an Arabic version of Indian style tea (usually with cardamom. OMG)