Nike isn't even on discover anymore sadly =\
Finishline is probably the only company that will credit jordan purchases with cashback. They probably have the best rewards program hands down as you can use it on anything online and in store.
That sticker is an "authenticity" sticker. However, these pairs were produced without authorization from Nike. So called "grey market" pairs. There are very slight differences in the production pairs vs these, but you can find these on the chinese websites that wholesale nikes.