Marketplace updates
Installation and Configuration
Because the cost of code does not increase as my usage scales. It's a one time sunk cost.
Amazon has recurring cost every month because you are
1. Paying for facilities
2. amortizing cost of hardware
3. Bandwidth (and the infrastructure to support it)
4. People to administer it
Basically, there is an ongoing cost to them an the more you use, the more it costs them as well.
Software on the other hand is a once time cost (putting aside support and future development).
Lets say it to 10 hours to develop that skin; its pretty bare bones. Once you wrote it, it's done. If the time you invested was worth, say, $400, then you need to sell 14 copies to before you start making a profit. Every copy after that is pure profit. You can sell 1000 copies and its still only 10 hours you put it. Pretty good product.
On the other hand, look at it from my side. If I'm going to deploy 1 cloud server, $29 is not a big deal. If I need to put this on every cloud server its going to cost me more and more. Any thing over 13 servers, It would make more sense to develop it myself.
In a service oriented cloud architecture, where you distribute tasks across many many servers it is not unlikely that you could deploy thousands of servers, even for short periods of time. This is the value of cloud and what enables you to scale. However, you are adding a cost that makes it uneconomical to scale to a product that is intended to help you scale.
Another way to put it is that you are taking something that had a fixed cost to produce but increases in cost as you use it. In that case it's better to write my own skin or risk paying thousands of dollars for of something that has a one time fixed cost.
I don't purport things should be free, just reasonably priced. This pricing model is not appropriate for its intended use. It does not cost you any more time or energy if I deploy the skin on one server or 10000 servers.
Hope that helps.