Coca-Cola was originally only available from soda fountains, at 5 cents per glass. The exclusive bottling rights for Coke were purchased in 1899 by a trio of entrepreneurs. According to the terms of the deal, the rights included the ability to buy Coke syrup at a fixed price in perpetuity. This meant that the bottlers could increase their prices to keep pace with inflation, but the Coca-Cola Company couldn't increase the price of their syrup in response.
In order to sell as much syrup as possible under these conditions, Coca-Cola advertised as widely as possible that bottles of Coke cost 5c, which made it very difficult for shops selling the bottles to increase the price. Consequently a bottle of Coke remained 5c for around 70 years.
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Coke doesn't taste as good as it used to in bottles. Really miss the old taste.