The factory workers didn't know what the right word was for 5 fireplace pokers was -- only the forms for one or 2-4. So to avoid having to guess (and possibly

The factory workers didn't know what the right word was for 5 fireplace pokers was -- only the forms for one or 2-4. So to avoid having to guess (and possibly getting it wrong) they made their request in a convoluted way. The bureaucrats didn't know what the correct plural form was either, so their reply is similarly odd.