A few posts down, I outlined the war rewards and pointed out that we are intended to get 5 of them a day. The rules are quite clear. Help as many friends as you want but you will only get a helper rewards for the first 5 during a war period (16 hours).
I helped in 5 wars and on the 6th one got the comment below. I've always assumed that the bonus is the loot item you receive for helping and I'm pretty sure this is the case contrary to some of the comments I've gotten about it.
There are no other benefits that could be considered rewards that I can think of. When you take out a target, you are simply told that you eliminated them. I don't see any cash or experience pay out notification.
Some players are able to collect an unlimited amount of loot items so I decided to see if I was able to. I tested this out by checking my inventory before and after being on the winning side of a war after I received notice that I maxed out on my rewards. I found an active war using the
Operation War Hunter Bookmarklet by Team Spockholm.
What was great about this war was that only one more person needed to be eliminated so it ended with my attack.
The helper reward was a Cataclysmic and I took a screen shot of it in my inventory before and after I helped and finished the war. In case you ask, yes I refreshed the page before checking the second time. I did not receive the loot item even though the notification told me I did. Now that I've shown that all players are NOT receiving an unlimited amount of helper items, the question should be addressed as to why and how some players do. I'll let Zynga figure that one out.
The next thing that should be addressed is a statement I made that was criticized by a few. I recommended that since you can only receive 5 loot items in the war time frame that you should only help with those wars that offer the best loot for your character. This joker below even called me an asshole! I think someone who posts anonymously is a coward and a douchebag.

I never said not to help your mafia members. You can save the window and go back once you finish your five. I would prefer that my own mafia do the same to me if I had a war that offered a crappy loot item. I would rather my mafia get stronger than win a war which would only yield me 2 crappy loot items. Remember there is no penalty for losing. Besides if your wars aren't being finished in a a timely fashion and you are losing because a few of your mafia decided to come back to you in a few minutes than you need to get a better mafia. I declared a war and refreshed the page. By the time I got to the war page again the war was over.
The same goes for most of my mafia members when I try to help from the news feed. Here is a request that was posted less than a minute before I tried to help.
It was said that I write subjective articles and that is 100% true. I do check my facts before posting any information and I have and will continue to be wrong at times. A blog is subjective by nature so if you don't like my opinions, I suggest you stop reading. My blog has been viewed over 2.5 million times and I would prefer that additional visits come from those who want to help and offer better advice than calling me an asshole!