We sit far enough apart (4 feet or so) that they really have to be "looking" to see my rolls. Most of the other players roll in dice trays, so I never see their rolls, either. When I DM, I sit behind my laptop so don't see rolls, either. I roll on a small side-table next to where I sit, so no one sees my rolls, then, as well.
If you are all sitting around a small table and rolling in a common tray, then sure people will see your rolls, but that is rarely the case in all my years of gaming--we've always had more "space" in that sense.