You know, I'm not even sure if that's Gaza to be honest... I just looked up riot pictures.
In any case, I still stand by what I said about the Israeli boarding party on the ship. I saw the video, from many different angles, and what I saw was clear as day... even though the footage was taken at night... and that was protesters attacking the men before they even touched down onto the ship. I saw them wielding pipes, chairs, and knives, battering and attempting to kill a bunch of guys armed primarily with paint ball guns. Nobody had to die, absolutely nobody. But the people on board that ship pushed the soldiers into a corner that left them with no choice but to fight back or die. People who were supposedly on a mission of mercy on board a ship of peace.
Just sayin'...
If you've ever been shot with a paint ball gun, you would know why they're effective crowd control. They're better than rubber bullets too, especially at close range, because there's a significantly lesser chance of causing permanent injury or death (of course getting shot in the eyes or throat is still dangerous but that's true of just about any projectile) tasers aren't a wise decision because they're out at sea. Electricity and water do not mix.
In short: Paint ball guns are actually ideal for this sort of mission because they're effective and non-life threatening. They're also quieter than rubber/bean bag shotguns which makes them even more ideal for usage inside a closed in area like a ship's corridors.
As for other loads... I'm not sure, though I don't see why they couldn't load rubber balls instead of paint balls... as long as they're the same diameter they should fire just the same. Plus, they would only be going at the same velocity as the paint balls would, which means they would still maintain the same non-lethal characteristics for the most part.