Everyday offers free cashback.
If you are offered any sort of cashback. Ie if you are offerred 10% cashback on a purchase. you do not really have to make a purchase. Just withdraw cashback to the minimum value. Ie if you have morrisons offer of £4.00 cashback then do your normal shopping. Like buy a loaf of basic bread and a 2 litre carton of milk and at the checkout be it manned or auto ask for £50 in cashback. The system will sense this as a purchase and award you £4.00 cash back.