When I had roommates we almost never shared food. Once in a blue moon we cooked something for everyone, maybe once every three months.
Living with my husband we sort of do what you’re talking about. When we have a rotisserie chicken he always eats the wings and some of the dark meat, I might get a drumstick and I eat the breast usually. I like the dark, but he doesn’t like the breast much, so I eat it. I have to get some of the skin early, or he’ll eat most of it without a care that I live in the house too. Lol.
Generally, we eat all the same food with a few exceptions. I think most of the time he eats without thinking about whether I want any of it, and I’m just the opposite.
Although, yesterday he asked if it was ok if he finished the pipián, which was unusual enough that I noticed it. I guess maybe because he knew I slaved the morning before making that dish, including frying the chicken skins first separately to make crispy chicken skins like chicharrón and setting those aside, and I made homemade bread, and sautéed some green beans. I also made delicious rice with some fat from the chicken skins. I was stuck in the kitchen for a few hours between cooking and cleaning. Not my gig! I usually cook quick dishes. I don’t know how some people spend hours in the kitchen daily.