Exactly. And since SC2 and Diablo3 are high profile titles, there will be emulated bnet servers and LAN loaders up and running for both those games within a week of their release. And those emulators/loaders will be pre-packaged in warez versions of the game.No LAN isn't a deal breaker, just an inconvenience.
The real question is why NOT include a LAN option in those games ? Using piracy as an excuse is absolutely retarded, not only will those games be cracked within hours of release - the pirates will end up getting a more functional product than legit customers and thus these kinds of decisions only end up inconveniencing the legit customer.