A difference in Olive Oil price mainly depends on the olive oil quality and the production method used to extract the oils.
Extra Virgin Olive Oil (EVOO) is more expensive to produce comparing cheaper regular Olive Oils. When we speak about EVOO manufacturing, the costs are higher at each stage of production, from olive tree grove to bottle. It is the highest grade olive oil which is unrefined and unfiltered. Based on market standards, Extra Virgin Olive Oil is without defects of aroma or flavor.
Virgin Olive Oil is made using a similar oil extraction process (cold extraction) as Extra Virgin Olive Oil. It is also an unrefined oil, meaning chemicals or heat are not used to extract oil from the fruit. Virgin Olive Oil is less expensive as it has slight defects in aroma or flavor and has to meet lower chemical standards.
Regular Olive Oil (or Simply or Pure Olive Oil) is much less expensive comparing extra virgin olive oil. This oil is typically a blend of virgin olive oil and refined olive oil (heat and/or chemicals are used in the process of extracting oil and removing flaws from the fruit). The taste of regular olive oil is light and mild.