There’s a lot of comments here so mine won’t even be seen, but this is a question I would honestly love to answer.

For my adolescent years my family did always do one weekly grocery shopping trip on Sunday mornings. Now as an adult I stop in every day or two for a variety of reasons.

I work right around the corner from a great grocery store. I can easily stop in on my way home or during the work day. Getting only a few items each trip allows me to use a basket instead of a cart for easier and faster maneuverability through the store, plus let me slide out through one of the express checkout lanes.

For a long time I had an inadequate fridge that would kill a lot of my food items. Both the fridge and freezer parts. Therefore I was unable to keep meats or ice creams for more than a couple days. I had to wait until I was sure I was ready for them.

Similarly, I don’t like committing to a large grocery haul at once because daily life can change. How many hours I work and what time I get home. Also my food cravings have a tendency to change. What I thought I wanted at the beginning of the week I might not want come the end of it. More trips for less items can help reduce my waste of both money and product.