Correct me if i am wrong, Usually the highest betters on both player and banker will view (if they want to) and in the process will "destroy" the cards.
Yes, spot on. The highest better for Player and Banker will get to peek at the card. The highest better can also refuse to see by letting other players to see on their behalf, or request for a Face Up (aka Croupier open card for you). If there is no one betting on one side, that particular side will be Face Up by Croupier.
Playing cards in such tables will be only used once. It will be sealed and destroyed after the game is over. A fresh new sealed deck is used every new game.

