There are clients out there that need specific versions of Adobe programs in order to have a functional co-working experience.
Not every company can afford a whole IT-section with caring for Adobe products the whole day long.

To be able to keep working within a team everyone needs the same version of Adobe products.

Now if one teammember decides to check out the new character animator and her/his older version of the all so important media encoder gets overwritten and it is not possible to install it again through the creative cloud manager, that is a real problem.

Why do we Cloud users always have to update every other day to the newest versions anyway? Why can't we decide for ourselves what we want to do? Are we not mature customers who may take their way of doing their work into their own hands?