It may be pure, but it is a blend of tens, if not hundreds of olive oils. And it's enough for one of the oils in the blend to be not-that-great (or outright bad) to make the whole blend less than the sum of its parts.
Just like wine, the best olive oils are mostly small-batch, made from olives from just a few orchards, preferably from just one olive cultivar that is listed on the label, and have a taste specific to that and their terroir.
In California, I found not bad oils at ~$25 for half a liter, which isn't too bad of a price, considering the exceptional oils could be double that.
I certainly don't buy such olive oil regularly, but I can easily tell the difference if I do.
Kirkland organic olive oil has won quite a few blind taste tests and awards. Something that many small batch wines cannot even do.