There are bonuses for fort control, guilds get resource/crafting bonuses and can sell their wares at a fort/resource point, there are a few 4 man dungeons that you can get access to at different points in the PvP.
List goes on really. The PvP is entirely opt in though, you have to join a campaign to get any of the bonuses and within reason you have to fight in that campaign for the crafting stuff etc.
After playing the beta as much as I could I can say this..
There is absolutely nothing about ESO that is revolutionary or even noteworthy about it. ESO is nothing more than a cookie cutter game copying aspects of just about every other major MMO out there. Graphically it is substandard compared other games that have been recently released. Character models are horrid, the voice acting is OK, and the story line is not bad but leaves the player at a total loss if they have no experience with the Elder Scrolls universe. The quests are extremely buggy, and on multiple occasions I or my friends would go to where the map says to go for a quest item and it wasn't there. We found the person we were to talk to in order to progress the quest chain on the opposite side of the island from where the map told us to go. Had we not been over there for another quest and just happened to see the guy standing there with the icon over his head we never would have been able to finish that chain. Many are completely broken rendering them almost impossible to complete, and at this stage the starter quests should be 100%. Many of the starter quests are just plain tedious and forget trying to run as a group in this game as they don't have much if any joint quests. More often than not people in my group would phase to another instance on so many quests that it was the same as running solo, giving the player a sense that they really want you out there all alone instead of having fun with friends.
The entire experience of the game is mediocre at best, while it looks OK there is not one single about it that warrants the $60.00 price tag, much less the additional $15.00 a month to continue playing it. Save your money for something better.