Hi Tracy-Ann:
Nothing is wrong with a few extra points. I think our primary role as teachers is to assure the student has learned the required material. I would not pass a student (via extra credit) if I felt they were deficient with needed course content. Perhaps in some courses it's not as important. But in others, (medical, legal, business), some material just absoultely must be mastered because the results of their "learning" may affect the lives of others.
Regards, Barry