And then there's the whole "having to murder people to fill the gem" once you've got it, of course...
Elder Scrolls is basically the Grand Theft Auto of the fantasy world. If there's a crime someone's thought up, you can commit it in Elder Scrolls. There's no denying that Skyrim has a villainous slant, after all if you join the Dark Brotherhood, you get an epic series of assassination missions, culminating in

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the Emperor himself


If, on the other hand, you turn them down, you get one mission to wipe out the Dark Brotherhood, and are rewarded with a shiny rock.

The same pattern shows itself in a number of quest lines, where the good option is either non-existent or merely perfunctory.