We are a household of two, about to be three when my daughter moves back home for a year. We eat eat very well and everything is cooked from scratch. I shop at Aldi and Lidl with the odd foray to Sainsburys and Waitrose (Waitrose Essentials (their basic brand) is very good and compares well to other supermarket basic lines.)
My friend insists that Costco is much cheaper, but my argument is that it might be if you have the money up front to buy , say, a year's supply of toilet paper, but if you are on a very tight budget then Aldi and Lidl are much cheaper and you can always pop to the other stores to get things that they don't stock.
What do you think?