You'd be surprised how many people don't know where their applications are located, and even that there is such a thing as a specific application location on a harddrive.
The distributions of Anime Studio and Anime Studio Pro for both Mac OS X and Windows come with an installer, that looks (or should look) for the installation directory of the main application, that could be anywhere on the system (even on an external drive, a network attached drive, thumb drive¹, virtual drive, etc.). AFAIK The Linux distribution even hasn't an installer, so it has to be installed manually, which is far from user-friendly.
So this isn't as trivial as you think it is.
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¹See this screenshot:

There was an error during the installation (because it expected a harddrive), but Anime Studio Pro just launched and seems to work as usual. I guess this also applies to NAS drives.