Because the way it is worded suggests that it is "rested xp bonus" perhaps? This is a standard feature in the western mmo, just like buyback features on NPCs.

And for the people saying this game will be "ruined" by implementing more WoW-features: I hate to point this out, but if this game was a Wow clone with the Final Fantasy name tagged on it, a crapton people would still be playing it (instead of the mass exodus we saw October '10). The game doesn't need more "WoW" per se, but it does need a hefty bit of westernization (which just so happens to include WoW within its sphere).

Playing a MMO shouldn't be this hard lol It's a large contributor to why it was free to play for over a year and why it requires an entire overhaul. That's just how it is.