Grocery Shopping

In the US, it often benefits the buy to purchase an item in larger quantities in order to get a better deal, more for their money. This is part of the concept behind Sam's Club or Costco, yes? Well, I can't trust the Irish sellers to abide by such a principle...which often catches me off guard, as their method just seems so counter-intuitive.
Here are a few examples:
1) 500g of bread flour is .87 euro. 1kg of bread flour is 2.19. Thus, I am better off buying two of the smaller bags as needed, rather than buying on larger bag.
2) 20 tea bags are 1.07 euro. 40 tea bags are 2.39 euro. Again, I am better of buying two boxes of 20 tea bags rather than one box of 40.
3) 6 eggs are .79 euro. 12 eggs are 1.69 euro. Ditto.
4) 750 g bag of frozen broccoli is 2.02 euro. 500 g bag of frozen broccoli is 2.15 euro. Now that one really doesn't make sense!

Thus I really have to watch the prices and sizes, and not assume the sellers operate on the American principles! I guess in Ireland you pay extra for the convenience of not having to return to the store as soon, whereas in the US you pay extra for have smaller portions of fresh items.

Another fact about grocery stores is that they sell out early in the day! So if you want meat or fish, you must arrive by 10am before the day's portions are sold. Also, shelves of dry goods are sparse by 4pm...you'd think we're in a Communist country! Okay, it's not that bad. :)