Organic EO's do always cost more, and 20 isn't that high compared to most. With EOs, the price is basically determined by a few criteria. First of all it's based on what amount of volatile oil can be expressed from what amount of herb/shrub/flower/spice . The harder it is to get the oil out, the more it takes to make a sufficient quantity of oil, the more it costs, which is why a rose EO is about $450-700$ an ounce.
Then it is based upon the method of harvesting. An organically grown product will cost more and a wildcrafted (meaning the product was gathered where it grew in the wild) product will cost the second highest.
Then it is based upon the method of distillation, which includes the consideration of the country of origins level of modern technology, or lack thereof. For instance, the Bulgarian Otto of Rose (otto just means oil) is going for anywhere between $450- $700 an ounce Chinese rose oil is running about $350 to $640 an ounce. Without taking the whole page, suffice it to say that the growing conditions and the distillation methods are different. (The French have the 2nd highest rose oil price and their method and growing condition is also different, but a good part of their price is inflated due to their reputation in history).
The constant between all of these, is that it takes a whole lot of rose petals (the Bulgarians actually distill 5xs and use the whole flower, but the rest just use petals) to make the EO. It takes 30 roses to make just one drop of EO.
While there may be other small influences in price, these are the main determining factors.
Sorry
to have written a book, can you tell I love EO's?