I think it's a little unfair to compare PAS prices to commercial
prices. Most PAS products are written by professors or teachers
on salary from their institutions. They get royalties from PAS,
but they probably never get reimbursed for the full value of the
time they invested. And that's as it should be, because they also
(we hope) get professional recognition, not to mention their ordinary
salaries. PAS prints nice manuals to go with the software, and provides
marketing, but otherwise their overhead is very low. In particular,
as far as I know, they don't hire professional programmers or otherwise
invest much in future products.
Commercial software is normally develped entirely at the expense of
the company. They have to hire programmers and pay their salaries
long before the product is ever released. This carries a lot of risk,
because the product may not sell.
There is, of course, a third alternative: faculty who develop their
own software can simply give it away, free. That's what I've done.
This has serious drawbacks, however: fewer people will know about
it because I'm not going to buy advertising space in journals. And
I can't list it as a true "publication" on my vita. For these reasons,
I've considered publishing some of my software with PAS. However, if
they're going to charge more than it's worth, then I'm no longer
interested.