Games have early access to make launch smoother. They entice players (via early time advantage) to pre-order so that they can gauge the initial server needs for a stable and balanced game population. The early access spreads out players' initial entry into the world to make that experience both enjoyable from a technical (lag) and gameplay (quest objective density/flow) aspect. The developers can also stagger early access a bit like they did with SW:TOR to make the experience even smoother. This also allows the developers to analyze more accurate population data to predict launch and future server needs. It doesn't draw any more money out of players (unless early access is limited to special editions only) as you either buy the game or you don't, and they could even have it save you 3-5 days of playtime as the developers/publisher could decide not to start the gametime until launch. Yes, the game could be bad, so the early access people could dissuade others from buying it before launch, but that is only a good thing for consumers. It is also highly unlikely because the early access people pre-ordered so will be hyped up already, which won't fade in 3-5 days. More likely, especially for Wildstar, players will already judge the game during open beta, so any negative reviews will be well before early access.