I wanted to buy a car...and I found that prices ranged from $10,000 to $500,000. :er:
Like most things, sometimes the price is inflated because of the brand name...but there is usually a reason why a particular brand name can charge a premium.
There are certainly some tangible things that may add to the price of a filter. Coatings and such. Sometimes the cheap ones aren't machined all that well, and might be sticky to screw in or unscrew...but it's hard to tell that until you actually use it.
My personal approach to something like this, is to avoid the lower price range but I usually won't go for the most expensive either...unless I've got a good reason to spend the extra money.