Buying groceries that will last a week doesn't necessarily mean you've planned for your week's meals. Planning takes into account all the ingredients needed for whatever special meal you'll be cooking. But point is you'll know the exact amount of 'something' you'll need before going shopping. That could be helpful especially if you'll be buying food that can spoil within a week because you'll either use it before it goes bad or you won't buy much of it and have to throw it out. I normally plan my meals and save a little cash each week.
I never plan my meals. It's always a sporadic affair with me, where I often don't even know whether I will be eating at home or out at a restaurant. Here where I live, it is cheap to eat out. So, often when I work until late, and feel too tired to prepare something at home, I just head for the nearest restaurant. I could never imagine myself getting up in the morning and planning my meals for the day or week.
I don't plan my meals but I do my best to use everything I buy and everything in the fridge before I go shopping again because too many people let food go bad in the back of the fridge and then end up throwing it away. I make sure to use all my produce and leftovers before they go bad. That saves me some money.
I don't always plan my meals. But right now I want to make spaghetti sauce so I am thinking about which stores will have the ingredients on sale. If I don't plan my meals, I plan my shopping buying what is on sale and what I have coupons for. I try to save at least 50% over the regular price of the things I am buying. But that means say sausage is on sale and I have coupons, I'll buy a LOT - say 10 lbs - and freeze most of it. Obviously that doesn't work for produce but I try buying that at the farmer's market anyway and next year I hope to grow a lot of it.
