The person explaining an exception has found where a simple rule meets actual work.

Every rule is a simplification of something more complicated, and the exceptions are where the simplification runs out. The person raising one is not being awkward; they are reporting from the place where the policy meets the job as it is actually done. That report is the most valuable feedback a rule ever gets, and it usually arrives sounding like a complaint.

When someone says a rule does not fit their case, get the specifics before deciding. Ask how often it happens and what they do instead. Either the rule needs a clause or the practice needs changing, and you cannot tell which without the detail.