How Extraordinary are the Ministers?

Dear Australian Bishops

Every Sunday at the time for Holy Communion, a number of 'extraordinary' ministers approaches the altar to help in the distribution of the Blessed Sacrament.  These are overwhelmingly female.  Given the small attendance at Mass these days, one wonders why they are needed.

But the question arises.  How can they be extraordinary?  They seem to have become quite ordinary.  And yet the ordinary minister would surely need to be a priest, who cannot be female.

I can understand that help might be needed in distributing Holy Communion if the priest is aged or infirm, or the number coming to receive the Blessed Sacrament is so large that the Mass might be unduly delayed.  But they are there, every Sunday. No matter the circumstances.

How can this contradiction be reconciled?