First, I'll respond to the comments about my comment. I apologize for over-simplifying my response. Let me try again.
I have found a number of websites which answer your original question. I haven't found that the true motivations for the #OWS movement [itself, not the people] are consistent with what you posit, i.e. people complaining about someone having more money than someone else. This may be a frustration felt by many Americans (in all of the spectrum of the so-called 99%). Here are some reading materials that may help you further your research. I would summarize their content, but I want to avoid misconstruing the message either through my own bias or my own ignorance. I am going to use a link shortener to save space (my own text takes up quite enough) and I am going to use a website that pokes fun at using a Google link to answer someone's question: http://tinyurl.com/cmpxd9f
Back to the OP. I'm not sure if this is a rhetorical question, because the image posted has clearly already drawn a conclusion.
The original post had the feel of a post that was purporting to ask a question, but really seeking to express a specific opinion. It's akin to this, for example: "What do people like about UFC? It's a bunch of half-naked, sweaty men rolling around." and then I link to this image: http://www.x929.ca/shows/newsboy/wp-content/uploads/2008/07/gayjiujitsutr2.jpg
Now back to the topic itself.
Protesting nothing? How about... the role of corporate money in elections (*unlimited* funding allowed by Super PACs); the influence of lobbyists (e.g. RIAA + MPAA influencing congress over E-Parasite and similar laws, as well as less techie laws); the irresponsibility and subsequent subsidization of large financial-sector companies; the fact that stock transactions themselves are not taxed in the US [but are in many economic competitors' countries], which makes gambling and speculation a free game for those with enough resources to play - even though it impacts the majority of US citizens negatively (e.g. high fuel prices); fair capitalism (e.g., not subsidies for oil companies, or manipulated currency values of China, or corporations paying little, no or even negative taxes); disproprotionate salaries of some government employees (e.g. congresspeople vs. regular Joes); uncompetitive wages and lackluster funding for public education.
Whether these are the stated objectives of everyone at various #OWS rallies, these are points that are consistent among the educated supporters. You could go to any sporting event and ask "What do you like about <your team>?" and the majority of people you run into will have an unsophisticated response, but some people will definitely be able to talk strategy, statistics and the technicalities of the game.
So, Dylan's question is a good one, if it's sincere. Why protest
? If sending letters, calling politicians and filling out Internet petitions had a real impact, people wouldn't take to the streets.