How the market works-supply and demand

I disagree with this article, the market should design the price of product by supply and demand. Nomally, the price of product has designed by supply and demand but some circumstance the government should be aware with unusual price, such as the higher usual price and lower existing price. Forexample, on the fruit seasons the market have fabulously with fruits, the supply more than demand so this reasons make the price of fruits very low. I think it's good for the consumers but it's very bad for the farmers. The government should interrupts this circumstance for help the farmer whose sell some fruits. Another example is the higher usual price, such as the price of gasoline. This is important product for a lot people in the world, if it stand in higher price how the pour people can buy it? This problem cause the higher inflation so the government should interrupts this higher price by many method, such as reduce gasoline taxes and establish the center of gasoline for sell in lower price.