Joining them could lead to possible account bans
DICE has confirmed by way of the Battlefield 3 Blog that apparently the PC beta has been hacked to allow additional game modes and support for as many as 128 players. As players know, the official beta is only Operation Metro in Rush for 32 players.
DICE has gone a step further by warning players that any play on unofficial servers using a hacked copy of the game could lead to possible account bans. We think joining any unofficial/hack server is going to lead to bans, and DICE isn’t kidding about it. The ban would not only affect the Battlefield 3 beta, but other EA games that are associated with the account banned, as well.
While DICE has admitted that they have tested Operation Metro in conquest mode with 64 and 128 players, they have admitted that with 128 players the server lagged considerably. Hence, this is the reason that they will not be offering support for 128 players.
It just seems that some people can’t leave well enough alone and have to try to push the limits, regardless of what the impact is to the community and publisher.