a boycott is meant to hurt the product's company. ALthough not buying a company's product does hurt it slightly, the intent is different.
Not buying something because it lacks something you want is simply not buying.
Not buying something because it is morally offensive to you or for the sake of others, is boycotting. Hell, you can even boycott a really awesome product. Say for example SC2 had lan, and everything you wanted and more. Say it was made in North Korea and you do not want to support North Korea in any way. That is a boycott.
However, in favor of this being a boycott, a boycott is sometimes used when a product is desired but something needs to be changed before you buy it, for example, moving the company out of North Korea.
So, in a way, you're both right. However, most of the people that want LAN play in this scenario, want it for pirating purposes ie: Installing one copy of the game on multiple computers for more than one person to play at a time. So it's slightly more "not desirable" than "boycotting".
