Joseph – So these folks would never eat (anything?) by a chasuna, or by a Kiddush, and they are never guests by anybody for Shabbos and Yom Tov? And they never eat anyone else’s mishloach manos? But they do buy processed food from stores, right?
I know people who don’t eat meat outside of their home (Rav Miller zatzal, whose yartzeit is today, was such a person). But not to eat anything?