The cinematographic film stocks are made to print to film, not paper. Projected film is capable of a higher SBR than a "paper" print - thus the greater dynamic range.
In addition, the process of printing to film stock involves an inherent increase of contrast. As a result, the initial cinematographic negative film stock is designed with a lower inherent contrast than film designed for printing to paper.
As I understand it, an optical "paper" print from a cinematographic negative film stock will be very flat - you will record the dynamic range, but won't reproduce it in an attractive manner.