[misja111]

The reason casino's add more decks, is so they can use them up only half the way and then reshuffle again. This way the chance of a big unbalance to build up of which a counter could profit, becomes a lot smaller.

Counters can still make a profit but it's harder. But there are some extra tricks they can use: for instance they can come with a group, set a couple of players at tables and have the others walk around. As soon as some table becomes profitable, the playing member will give some sign and his colleagues will sit down and play at his table.