Ok, I responded to the blog post, but I'll copy and paste here. Thanks for the recognition Terp.
I think there is an additional piece to consider which you touched on. In general, DNN modules are only parts of an application. I know there are some modules which are close to complete applications by themselves, but they still run on the DNN framework. Some companies combine many of these components to make a total solution for a customer and I think these companies price out their time into the total solution. The reason I bring this up is because the comparison to Community Server enterprise is not really fair with individual modules. To be more fair, a Community Server Enterprise license should only be compared to a total DotNetNuke solution which should also include support after the sale. That way the end user should be returning to the person they paid to bring together a total solution who in turn may or may not need support from the commercial module developer. If the solution developer is any good they will need much less support from the commercial module developer.
The difference with this in the DNN community is that we have evolved the DNN ecosystem into a vast Do-It-Yourself mentality. That is not all bad either, but it brings with it a lot of people who demand more for less, and they want it to work in their own unique situations.
I don't think modules are too cheap, and I think even if they are only $50 a customer still has the right to expect a lot out of them. Consider going to Radio Shack and buying some separate pieces to build your own robot. Would you expect every piece to perform it's function as advertised only if it costs over $200, or would you expect to get a lot out of a particular component even if it only cost $20?
As commercial module developers we should be expected to deliver more for less, and make our money to stay in business on volume. If we spend time supporting our products then it will in turn make our products more valuable to more users. Don't get me wrong. The customers should not demand that the product do something that it was not intended to do unless they are willing to pay a premium for custom work, but if we create great modules that perform above most people's expectations then we can afford to sell them for less money.