If I were to take a guess it'd be they choose a lower fov to:
a - render less things on screen aka, easier to get better performance
b - need to reduce the viewport so the sub-720p rendering doesn't show as much
c - are putting in their respective 'artistic visions' which, by the looks of other art fields (such as a blank canvas being considered art) can be a good or a bad thing.
d - all of the above.
A is not entirely accurate. You may think there is less, but almost all games use LOD for models. The further away you are, the less complex the objects are. The same works in reverse. So by having the view closer to the action, the engine may actually draw more complex objects and models.