I do not think it is gross to reheat and eat leftover meat which was cooked and served and not finished---but no that is not what we do. My family would not find just a plain piece of meat appetizing, so it would not be served at my house. I might well cook some meat as an ingredient in a future meal at the same time as cooking the meat for tonight's meal, but the falvaours/spices would be different. We would not enjoy unflavored meat which could then be reaosnably used later in something else---so, for us, once it is served "on the table" it is really meant for consumption that night (if it is cooked/mixed. Plain raw veggies, fruit, etc can go in and out as fillers).
I do tend to shop more often than a lot of people---I like fresh veggies, and minimal waste, and our schedules are all so haphazard, if I bought food for a week at a time, I'd have to guss at who all would be home when and end up with food going to waste, or havnig to run back to the store anyway.
But, I don't buy meat every day even though I prefer not to freeze it (I don't like how that affects the texture, plus then I would still have to know by the night before who all will be home for dinner the next night, which is often not possible in our family). A package of meat bouhgt at our local store usually has 5 or so days of freshness in the fridge.
So, the way we cook: maybe I pick up two of the standard packages of chicken breast "schnitzle" (smaller, flat pieces of chicken breast) at Aldi on Wednesday. They'Re 400 gramms and normally have 4 pieces in them.
Maybe on Wednesday DH messages late afternoon to say he is roped into a bussiness dinner and will not be home, so DS and I make his favourite pasta dish, using two pices of chicken. I put the other two pieces from the open pack, raw, into a container in the fridge for another day.
Thursday we have fajitas. I use up the open chicken plus pull one from the next pack.
friday DS goes out with friends and isn't home. Perfect time to make pot stickers that DH and I love and DS doesn't. Plus, we probably have cilantro leftover from fajitas so we can use that up (or most of it, putting the rest on pizza on the weekend)
1 to 1 1/2 pieces of chicken is about perfect for the filling for those when it is just DH and I. I might decide to cook all three pieces of chicken remaining, cutting one in half first and seasoning the pieces we will not use in pot stickers for BBQ chicken pizza toppping on Sunday, or I might put the raw chicken in the fridge and cook it while the dough is rising on Sunday.
No left overs. No waste. No shopping for meat daily. (yes, lots of chicken---I don't eat pork or beef, we tend to eat a lot of chicken). Not how you do things, which is FINE, but not wasteful either.