As the recession worsens, more people are reverting to coupons to try and save money, so coupon use is rising quickly. As to cost of flyers, in bulk they are under a penny a sheet, so this is a very cost effective mainstream method of advertising products. There is a science to it, coupons will be effective for a couple weeks usually, and you will never see same item on sale if coupon campaigns were launched at same time.
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