I'm pretty sure there would be a heck lot more buyers, even if there was no LAN.
If there was LAN, and it cost $109, no one would buy it. d'oh.
So the reason why there is no LAN is because it costs $109?
If there was LAN, and it cost $50, people would buy it.
Look at WarCraft 3, Diablo 2, even StarCraft 1.
How many people bought CD keys online from Blizzard, because they wanted to go on battle.net after experiencing LAN? Quite a handful.
Cheaper the game is, less incentive there is to pirate it, more incentive to buy it.
Especially if the online service (Battle.net) offers more things compared to LAN.
Example of online service versus LAN? Oh I dunno, maybe some units require online version whereas LAN is restricted to basic units? In this way, LAN would still be an alternative, albeit an inferior alternative to online service. Not that I am suggesting that units be based on whether you play online or not. A game mod would probably fix that anyway (look at SC1 and D2 mods).
Or perhaps LAN be restricted to 1v1 only. This would be a welcome fix as compared to the current offline campaign. 2v2 and more would require online version. And trust me, many people want to play games which are bigger than simply 2 people.
