I assumed because the base cards are numbered on the front. Most companies use the same numbering location for the cards in base sets that also have promo or variation sets. Based on precedent being set on hundreds of releases, why should I assume the numbers are on the back?
You could have easily posted in the forums asking me to email you about a question instead of trying to call me out and make me look like an idiot with your sarcasm. I didn't close it with malace towards you, I just wasn't certain where the cards came from and you know that if there is no certainty of origination the card does not get listed until it can be verified.