Looking in my wallet i have half a dozen cards, so whats another,i have nothing to hide.
If it keeps all the undesirables out of this country and lowers my taxes-great.
It's not the cards themselves, it's the associated massive database of information about us all, and the inevitability that "show me your ID card" will become a stock in trade for every council jobsworth everytime they want to put you in your place.