Quoted from jfh:
Agree in general. But it was known at least at Expo 2016, if not before, that a limited number of Premiums would have signed cards in addition to the SLE/LEs.
When Adam West was in Chicago for Expo 2016 he also stopped by the Stern factory and signed 500 cards to be used on the LE/SLE games. Since there were 240 LE's and 80 SLE's that left 180 signed cards that could be used for the premium machines. This was an incentive to buy a premium right away and maybe get one of the signed cards from that first run.
I don't think anyone expected Stern to hold back some of the cards for later use. So I can see why an early premium buyer might be annoyed that they didn't get a signed card but someone that buys the game 2 years later got a signed card.
If you really want a signed Adam West card for your game you can always buy one on eBay and maybe if you are lucky it will actually be authentic. Burt Ward still goes to conventions every now and then and you could get one from him for around $100. Or if you are a fan of the original Catwoman, Julie Newmar, you could send a card to her to get signed. I think she still sells signed stuff for $35 on her website.