Your analogy with apprenticeships does not work. A plumber is working as a plumber, someone who has not done a plumbing apprenticeship cannot do the job.
A degree was not a requirement for your job, and having one does not mean you are any better equiped / more efficient as a Clerical Officer than the person beside you who joined with a cert/ straight from LC/after a back to work course.
Having said that, the degree will be helful in applying for promotions.