3-for-2 or 3-4-2
Three for the price of Two is now-days a common way for a store or outlet to encourage a person to buy three items of any one product instead of just one.
A bad outlet will simply have calculated the total price of three items, and charge you that price for two, making you think that you have got a good deal, but all you will have done is buy three instead of buying one, and with some perishables, you will end out having to throw some away as you couldn’t consume or use all of them before their ‘use by’ dates.
The better outlets will still charge you the price for three, but will reduce the profit margin by a small amount. You will still have purchased more than the one item you intended to buy, therefore increasing their profit margin.