I buy in bulk or large quantities when on sale as well. Unsalted butter around the holidays somehow always ends up on sale and I can rarely find coupons for it so I stock up and freeze it for my Toblerone shortbread cookies.
I am big on local produce in the summertime including my own garden. I grow mostly herbs and then wash em, chop em up in the food processor and then freeze it in tupperwares to use all year old. Mostly coriander, basil and oregano because I just love those. I also dry mint in the summertime to use throughout the yr but we put that in tzakiki sauce. I also buy cleaned garlic in the reduced (mostly Chinese supermarkets) get a huge bag of cleaned garlic and then food processor again and then freeze. Makes it easy to make a quick sauce at home when all the herbs and spices are fresh and frozen. I buy bushels of tomatoes in the summer and make my own tomato sauce and freeze in ziploc bags. Easy to store and easy to defrost when needed.
I buy most of my meat in bulk from the butcher and freeze it. All in freezer ziplocs, I will not settle for the no name brand when it comes to freezing meat, it is not worth the savings in bags to find a freezer full of burnt meat. For the chicken I precut them to the sizes I need (usually for stir fry) and flatten the bag and freeze, again quicker meal prep times and defrost times.
I also cook 2 or 3 meals out of 1 big meal. If I overdid it I will freeze it because well I have my 3rd baby coming in January and will need some prepared meals then.
One thing my inlaws laugh at me about is during holiday meals. I always ask for the bones when we are done with the turkey. I will bring it home and boil it at least twice and freeze the broth. Nothing like turkey broth to make a killer soup in the wintertime.
Otherwise everyone else is right and remember you don't want to go too cheap on your family...just enough so they appreciate what they have. My husband grew up very poor in the Philippines, they had meat from time to time on the table but a really really small piece. He was taught to appreciate the taste of that meat in every bite, even if it meant just touching the fork to it. He has since taught our kids to appreciate everything we put on the table. Mind you our children are only 4 yrs old and 2 yrs old but I think kids nowadays take things for granted and expect the world...we need to change that