The number of possible combinations of cards in a standard 52 card pack is so large that there is very little chance that any two packs of shuffled cards that have ever existed have ever been in the same order.
52 factorial is a larger number than the number of atoms in the observable universe.
If you divided the universe's mass into 52! parts, each part would contain ~1x10^13 atoms. Which, as far as solids go, is not visible to the naked eye. Which is still quite mental..
I bet there are certain shuffled combinations that repeat. like, take a new deck, divide perfectly in half, do one perfect riffle. that has probably happened more than once.