Hi Linda:
EC is usually regarded by many as unfair, adds to grade inflation, and (as you point out) allows students to substitute required work for prefered EC work.
But I would agree that if whole chunks of material is being missed by the majority of the class, then reassessment of the class (objectives, timing, sequencing, lab, media, resorces, delivery style) ought to occur to assure the maximum use of the students time and learning is being achieved.
Regards, Barry