kryptonjohn:

 

I assume we are referring to bulk bins where you shovel out loose material such as nuts into a bag and pay by weight? Strangely these often seem to come out *more* expensive than buying the same thing in a packet ???

 

Yes - I've seen that too.

But there's nothing strange about it - it's how the system works, and you'll often find that the cost per kg price of common products is quite a bit higher for larger pack sizes - it's cheaper to buy 2 x 1kg packs than it is to buy 1 x 2kg pack.  Countdown print the cost per kg or unit in small print on their shelf labels.  I actually doubt that most people bother to read them - even though all the arithmetic has been done - for example when it starts to get complicated when manufacturers obfuscate by packaging in odd sizes - take a look at "refill" plastic packs of coffee vs jars - there's less in the plastic refill than the jar, and it's often cheaper per kg to buy the jar, despite the sticker price being lower for the refill.