There is more to a link than nofollow. A link is content on the site. If they deleted nofollow on (some) links, they should require a higher price. Isn't that natural? Isn't that the nature of a free market economy?
The only thing you can blame them for IMO is how they inform webmasters about their policy. Could that information be better?
Example is this an unnatual price policy for a site with high traffic?
- Price month for a link with nofollow USD 10.
- Price month for a link without nofollow USD 50.