6. To entice customers away from competitors, Red Label supermarkets have begun offering discounts on home appliances to customers who spend $50 or more on any shopping trip to Red Label. Red Label executives claim that the discount program has been a huge success, since cash register receipts of $50 or more are up thirty percent since the beginning of the program.

Which of the following, if true, most seriously weakens the claim of the Red Label executives?

(A) Most people who switched to Red Label after the program began spend more than $50 each time they shop at Red Label.

(B) Most people whose average grocery bill is less than $50 would not be persuaded to spend more by any discount program.

(C) Most people who received discounts on home appliances through Red Label’s program will shop at Red Label after the program ends.

(D) Since the beginning of the discount program, most of the people who spend $50 or more at Red Label are people who have never before shopped there and whose average grocery bill has always been higher than $50.（E）

(E) Almost all of the people who have begun spending $50 or more at Red Label since the discount program began are longtime customers who have increased the average amount of their shopping bills by making fewer trips.

没有人讨论过B，我认为，打折的目的就是让不想超过50的人也超过50元，为什么B不对呢？如果不超过50的人即使打折也不愿意的话，打折还有什么意义呢？望赐教！