[dirtyroboto]

I know many of the readers here are too young to understand shopping as a finacial skill but in Japan like other countries it is a skill that can save you much money in the long run.
In Japan you will find competing chain stores that will have some things lower and some higher then their competitors.

In some shops you will find that beer is cheaper while pasta is not, fruit in some places is a bargan while in others is a rip off.

In Japan you need to look at prices in different stores and make the right buys in the right places. It is very bad to buy all of your stuff at the same store for convinience. you will end up paying more for the cheaper items by virtue of paying over the odds on other items. This is how they sucker people.

In most super's they will also have a discount basket where items can be bought cheaply as the expiry date is due. BE AWARE! these can also act as traps for the unaware. You might only be saving 20 yen on a date difference of 2 weeks. Pick up the item and find its fresh buddy and compare the price. Sometimes a great deal is found and sometimes you will end up putting the bargan back where it came from.

Household items, such a plastic stuff, cleaning, bathroom, kitchen and so on, can be bought at 100 yen shops for 105 yen (inc tax). These items bought in a super will in most instances be 150 - 200 yen and above.
Always check the 100 yen shop first. Spend a long time browsing as you never know when you will see the same item in a super for much more.
For me I had bought some spices for 230 yen ect. only to then see the same in a 100 yen shop.

My advice is to pick 5 things that you buy often and then compare the prices in various supers. You will soon understand the advantage you have by doing this.