I think some are because mainly its due to the fact they belonged to the first group of developers who had lots of money and time invested in their money making ventures.
For example, Steinburg who were there right from the beggining. And if you have noticed, Steinburg has changed hands a number of times, and they would certaintly fall into the trap of not being able to drop their prices that easy.
Whith the appearance of Synthedit for example, many others are able to make their own synths and effects, and there are a lot about. To charge a high price for something these days I think, it would have to be something special and unique that you probably could not do whithout.
I think you have to be pretty good these days to earn a good income from software. Its a buisness and you need besides the products to be set up very well.
Tracktion for example, its under on going devlopement and priced well, it gives support and has a workable web-page, they take pride in maintaing a loyal customer base, and you can purchase easily and quickly.
I remember recently watching a documentary on TV about pirated video movies. And their answer was to drop the price of a movie DVD that much that it would be not be feesable for the pirates to make it. Like it is easier for you to purchase the DVD at your local shopping centre than take a journey out to the pirate's and buy a substandard copy.

