I don't ask my users to install Visual Studio, IIS or Windows Server 2012 on their boxes. I kind of think asking them to install SQL Server is similarly foolish - particularly since now you have to pay for 1 SQL server licence per user rather than 1 per organisation.
If you're going for edge case business scenarios as your rationale as to why RT isn't a good choice, perhaps you should be considering whether Windows8-Pro is more appropriate for your business needs than Windows-RT.
Windows-RT is never going to be a good fit for where you're forced to use desktop applications, supporting services or plugins to existing applications and can't provide equivalents as a web-service.
RT vs. Pro really isn't at issue here since the database discussion is about the limitations of the WinRT / Store App API which is on both RT and Pro devices.
After reading the drooling vitriol in this thread, I'm beginning to think that most of the issues you folks have with WinRT is that you feel lied to by a marketer months ago because you didn't have your critical thinking hat on.
I don't know what marketing has to do with it, but, at least as far as the database issue being discussed here, a valid criticism of the limitations of the WinRT API with regard to database access was brought up and it didn't seem in any way vitriolic. What I find amazing is that people on this forum can't possibly fathom an application that downloads data from the Internet, stores it in a local database, and then does reporting and analysis on that local database. Really?