the Windows Server Licenses are the expensive part
And you also get credits from Bizspak, that could be used to apply to offset AWS licensing.
Too much drama. Here's pricing for m3.large:
Red Hat: $0.193
Windows: $0.259
Win + SqlWeb: $0.367
The cost is worth it if it saves you multiple employees worth of development work or administration overhead, and in my experience it does. The pricing is also (surprise!) negotiable. At Loopt, our annual software licensing cost was well under the cost of one developer, and this was before BizSpark.
But you can see why people get some sticker shock: $14,256 on their website for SQL Server 2014 enterprise (per core!) http://www.microsoft.com/en-us/server-cloud/products/sql-ser...
However as you say, you could easily get a 50% discount on that without having a big SQL Server farm.
No bizspark required.