Perhaps this has been covered before, but HF (at least the one near me) will accept a smartphone image of a current 20% off coupon. They will simply enter the numbers from the image in the computer and the discount will be applied.
You get the discount and you retain the coupon to use again and again until it expires.
e.g. I used this image at the same store twice, once on Saturday and again on Sunday.
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I know that it says "Original Coupon Must be Presented", but I guess their definition of "original" is pretty broad based. ;-)