And another note on contracts, I do not get into the queue at Tescos and when I get the bill, just tell the check out till operator what I am prepared to pay for the goods. I may not think half a dozen eggs is worth 97p, but the price is a "contract" to buy.
Not quite. The price is not "a 'contract' to buy".
The price displayed for the goods is merely an "invitation to treat". When you go to the till, contractually, you make an offer to purchase the goods which is then accepted by the retailer (which in actuality is done without saying anything).
There is nothing from a contract law perspective from you offering to pay at the till different price for the goods than that displayed on the shelf.
It's called negotiation.
