Here's what I discovered in my search to solve this riddle. ESRI has created an executable to programmatically install data licenses (*.sdlic files). The executable is named "DataLicInstall.exe" and it ships with ArcGIS for Server. It does not ship with any ArcGIS for Desktop products at this time (but it does work with them). I've posted an idea at here asking ESRI to make this exe part of the ArcGIS for Desktop install. Please vote it up if you need the ability to programmatically install Data Licenses.
---- How to install ESRI Data Licenses programmatically ----
If like me, you are lucky enough to have a copy of ArcGIS for Server on hand, you can locate the "DataLicInstall.exe" on a system installed with ArcGIS for Server at:
It can also be extracted directly from Data1.cab located in the ArcGIS for Server Setup Files.
Once you have your grubby little hands on the "DataLicInstall.exe", copy it to:
C:\Program Files (x86)\Desktop<version>\bin64
on your system installed with ArcGIS for Desktop. ArcGIS for Server does not need to be installed on this system.
Open a command prompt and call the exe using the following parameters:
<path to DataLicInstall.exe> <path to *.sdlic>
"C:\Program Files (x86)\ArcGIS\Desktop10.2\bin64\DataLicInstall.exe" C:\DataLicense.sdlic
In my case, I was installing the ESRI Business Analyst Data License:
Unfortunately, I won't be posting the exe anywhere since it is ESRI's IP and I don't have any desire to be on bad terms with them. I imagine though, if you really needed this capability and you talked to ESRI Tech Support and showed them this post and that it was possible to do this, they would send you the DataLicInstall.exe (so long as you're current on maintenance)