In no way would I ever condone rioting ( I believe, for the most part, it's counter productive), but I'm curious to find that many people don't understand the impetus behind the anger of the poor British infiltrating their own streets. And though David Cameron has instituted specific austerity measures, which gut social services, in an attempt to balance the budget, it speaks to the overall problem of neglecting the lower classes in the name of the health of the wealthy. Simply put, it's much easier for governments to slash entitlement spending because the poor don't have the political capital to really do anything about it, where as the upper class does (and this is NOT only a British problem. Watch out America. We should be taking a lesson from this.)
One doesn't need to understand economic policy to see the root of the problem, actually, it's common sense. If you, as leaders of the community, turn your back on the lower classes by cutting the social services they depend on, while removing the infrastructure of order (in this case, cutting police force pre-riots), you foster a sense of being abandoned. And when people feel ostracized from the community and then struggle to fill their basic needs, they become angry and start seeing the world in stark black and white. When this happens, they clearly no longer see their neighborhoods, community, and leaders as part of the solution, and instead, they become the entity to blame for all that ails them (and there is some truth to this). Thus, they riot against the exact thing that once nurtured them in a, for lack of a better word, cry for help.
It's simple, if you keep people happy and involved, they won't trash their neighborhood. It's like a dog not wanting to shit in its crate. If it feels safe in its environment, it won't try to ruin it. In society terms, if you keep the middle class/lower class content and show that the community is making an effort to take care of its own, then there is no reason to riot. These riots aren't happening because people are bored. They are happening because people are angry. And they are angry because they feel left behind. And I don't blame them, even though I would, personally, take a different course of action.
The solutions to these problems aren't impossible, despite the world's government's clueless attempts at fixing the issues. Unfortunately, it would require the world's selfish, greedy society to completely switch it's world view to one where they understand that a strong community, one that vastly shares it's resources, is a happy one. But, instead, we'll just be fed lines about higher taxes being job killers as if taxes are some alien beast from Mars that feeds on the soul of humanity. The only reason higher taxes may effect business and hiring is greed. The idea that higher profit, outdueling your peers, is somehow virtuous.
And until we eliminate the culture of greed from society, this will be a continuous problem. But, obviously, I'm not holding my breath.