Yes - you have to specifically tell the person serving you that you want the discount.Re Amex cards. Last season I'd get either 10% or 15% discount. Maybe the till I use.
Also got a half price new home shirt for buying my ST with Amex. Disappointed though when I went to the club shop during the week that the 10% is only valid match days so put a T-Shirt back on the shelf.
If you do have a card you have to show it when ordering, but you don't have to use it so if you've an old card get it out.
No idea why it’s not automated