Miriam,
You've made a good point about EC. I don't have issue with students doing something above and beyond what's required, it's the subjective grading and/or awarding of points for that effort that causes difficulty. Unfair, favoritism, and grade inflation are the reasons/complaints students can cite when EC is given. Policcies vary, for me, I just avoid the whole process altogether, as over the years, I've found strong students won't need it and waeker students ultimately are not helped by it (EC may raise their grade but does little to assist in their learning).
Regards, Barry