When I was a kid, fruits like strawberries, cherries, kiwi etc were not very common. They used to be available in very few places and they used to be quite expensive. Today a lot of people has seen the potential of these things and have started growing them. There a lot of people growing these fruits as well as other things that were not very common like broccoli, mushrooms, baby corn etc. Now strawberries are cheaper than apples but still they "exotic" tag has still stuck and they are usually sold in cardboard boxes that have a packing of leaves underneath to give an appearance of a greater quantity.