What Is With Brinklink Limits

So I think most people agree that all the best Lego sets now are Bricklink sets. So what is with the limits they put on production? Never more than 30,000 and limits of 2 per household?

Why do they not want their best sets to be sold in high quantities? Why not sell a million? Normally companies want to make more money, but for some reason Lego seems to want to hold back their best stuff.