About a decade ago, there was a huge kerfluffle about making the plugin directory include pricing and payments (like an app store). Matt was hugely against it. I think they did themselves a huge disservice. Pricing is opaque until you install the plugin, often requiring you to go "off site" to install the paid version (or it silently uses a different plugin repository). Lastly, there is no quality control or even ensuring that best/ethical practices are being followed.

So, you end up with this scummy feeling every time you install a plugin and discover its pricing.