Your assumption is unfortunately too simplified. There are a lot of factors at play that you haven't considered so far:
Let’s look at unrefined oils first:
For them to be marketable, they must be free of off-flavors and overall of a higher quality than what goes into the production of refined oils. The yield is typically lower and production processes (e.g. cold press) can be more complicated and thus more expensive. Their shelf life is significantly shorter, which is also a cost factor, as producers and resellers can store their stock for only a limited time.
Refined oils may be "less nutritious", but for many applications that’s irrelevant or even counter-indicative. Refined oils typically have a significantly higher smoke point (which is a use case where your "good" unrefined oils turn "bad" very quickly), so they are more suitable for high-heat uses like frying. While the refining is an extra step in the production process, you can make refined oils with a higher yield, faster processing and higher tolerance with regards to the input, which overall is typically cheaper. The resulting relatively neutral flavor makes refined oils way more versatile (your probably don’t want your fries to taste like coconut) for those applications where you need an oil, but not a prominent flavor.
In short, you want probably both kinds in your kitchen - the refined as the workhorse for frying and cooking, robust, cheap and heat-tolerant, the unrefined to add flavor to your dishes either during gentle cooking or added at the end, some oils are specifically used more like a flavor garnish, e.g. pumpkin seed oil.