I have the penny sleeves. I shuffle them long side to long side.
The only issue I have is when someone tries to fingernail/crush the card to pick it up off the table instead of just simply sliding it off the side of the table.
They do tend to stick in warm weather but a pile shuffle to seperate them all will take care of that.
To pick up cards easily from a smooth tabletop, make a one time small investment in a piece of felt. (I use 24" x 24" for Dominion...)