Although supply and demand are the two factors that ultimately influence the standing of the price of goods in each area/country, there is another big factor that we should always be on the lookout and that is individuals who have the money and influence to manipulate the market. Market manipulation happens all the time and everywhere (in fact there is a more thorough discussion about this in a different post if you want more insights about it:https://bitcointalk.org/index.php?topic=5465009.0). Additionally, market manipulation can be done by different individuals or organizations such as big companies, wealthy and influential business individuals, and the government. Naturally, the main reason why they do so is due to the benefits market manipulation gives to them such as a rise in profit and sales. As to how we will be able to reduce the price of goods, the answer might lie on the government as they have a good hold on market manipulation.
Of course, supply and demand are the two main factors that affect commodity prices everywhere. Whenever the price of a commodity is increased, its supply decreases, which causes its demand to increase and the price to rise. Often in such a situation the influence and power of the mafias play a major role, no doubt such manipulations are everywhere, but where the laws are strong and the government has a grip, such people cannot easily create such a situation.In a society or a place where law and justice are weak, such cases are common.
I don't know what the legal situation is in Nigeria, but there is no such thing as law and justice in our country Pakistan. Courts are only working to protect powerful people and capitalists. Due to which the prices of food items are often increased by creating food shortages, but no one takes steps to stop them. You are right that where the grip of the government is weak, the powerful mafias also have a strong grip,and always increase the prices of things at will.
Often such influential and powerful people have a lot of power at the government level and many of them occupy high government positions, which makes it difficult to take action against them.