SB is a pvp game, that's a statement.
You can not going into Bg if you don't want, but some zones are neutral zones where FvF exist.
There's different way to up your characters, so you don't really need to go in pvp but you will probably want to take some points to add the pvp skills in your bar.
From my point of view (i'm a pvp player) skipping pvp in Sb is sad, because it's fun (i'm not judging, just my personnal opinion).
If i can motivate you like that . The better rewards are on WB and chest of neutral zones