One time I couldn't find lamb shanks at the local Ralphs for the seder. The manager, who was Armenian, told me in a low voice to go to Super King. They have plenty of lamb shanks because it's a popular Armenian dish.
That was the first time I went there. You could plan your travels around the foods that were there. Armenian, easter European, Latin American (not just Mexican), various Asian foods. One thing made me laugh: There is a brand of various veggie concoctions in glass jars, very popular with the Armenians. It's a brand from Bulgaria and the name is Zergut. I doubt if anyone else in the market knew what it meant.
Anyway, you shouldn't have to put up with rudeness in a store on the part of the workers.
The immigrants here assimilate pretty quickly. That's because of the surrounding communities. If they want to speak to others like them, it's a trip to Vancouver, over the border.