Plan ahead. Spend loads of time on preparation.

Buying for more people means buying in bulk, where you would throw that away with fewer people.

The more thrifty people around us plan out their meals for a month, to make sure they can buy in bulk deals, and freeze meals/products for the end of the month. They will use the ingredients of every dish and combine them into other dishes with different spices/herbs/flavors to create some interest. The variety within the season is sometimes a little lacking, but overall it's still balanced over all the seasons.

Frozen seems to be a good choice left or right. Flash-frozen meats, seafood, fish, fruits, and vegetables are considered close to fresh, but usually cheaper. If you have the space at home to store leftovers, so you can buy in bulk.

Haha! It's mostly the fear of not having a backup when something goes wrong, I guess. We would do the same when we were in India, lavishly overspending, knowing we have our parents financially bailing us out whenever needed.