Why aren't hydroponic crops more common?

Hydroponic systems are expensive and time consuming to maintain. Nutrient levels have to be constantly checked and kept in line. Also the lights used for hydroponics use boatloads of electricity. A 1000 watt light kept on 24 hours a day can use 50 dollars a month in electricity. With outdoor crops, the soil provides most of the nutrients and the sun provides plenty of light. The only thing that must be provided is water if there is not enough rainfall. Hydroponics for public food consumption would drive the price of food through the roof.