More on this conversation:
A more plausible variant could be that organizations can choose which of the office types their users can choose from - which is equivalent to the ability to hide certain office types for users of a particular organization. This is more plausible because you would have each type only once, but some of them may not be used by all organizations.
That would, though, require a many-to-many relation between office types and organizations, and fairly complex filtering when generating the form widget - however, it would solve the Admin case, because there it would simply imply no filtering.
But still, I doubt that this has as much practical value as to justify the additional complexity by default - or, by consequence, the need to work around that complexity when you do not need it (which would be the majority of cases IMHO).
Thank you to Dominic for these and the prior excerpt thoughts.