i've bought amazon, staples, and one other card i don't remember. as the member above me mentioned they do give you "Points" per purchase, and these points are like 100 points/ 1$ and you can redeem them on your next purchase
You don't have to print them off.....I've been buying gyft cards constantly. You get the app, and pull the card up on your phone attthe retailer. They scan it. Easy. Takes 2 seconds. Also, you can use the codes online if the retailer sells online. (Burger king doesn't). I've bought from like 17 retailers on gyft, no issues ever.
I should have clarified that i was talking about the staples giftcard. i also don't have mobile data because i'm a cheapskate.