So, are Nike's logo or designs actually stored on the etherium blockchain? My understanding is that most NFTs just embed a URL. If that is the case, the retaile

So, are Nike's logo or designs actually stored on the etherium blockchain? My understanding is that most NFTs just embed a URL. If that is the case, the retailer could simply change the content hosted at the URL. The NFTs would be unchanged and the coupons could still be redeemed. Everybody wins.