Change what you eat err drink.
Buy subsitutes example frozen concentrate oj rather than OJ
Plan your meals out to cordinate loads.
If I had a dog, I would take him to the store so he can haul his food home.
Put the famila to work give em some panniers or something.
Myself I shop every week or every 3 days depends on how much I want to shop versus haul.
A bag of rice, oats,potatoes, flour, sugar can last a long time.
I myself just plan and use a back rack with trunk and back pack or just painers.
2 breads, 2 bags of corn tortilas, 4 soups, 2 jars of somethin. 1 bag above, and room for two additional small items.
I would use a trailer if I lived farther.