Your own link mentions that possessing a large array of cellphones is actually cheap

Another reason why people often opt to use click farms is that they are incredibly cheap. Many businesses will run online social media marketing campaigns on Facebook and Twitter in the hopes of increasing their followers. However, sometimes they aren’t always as successful as they would like which raises the question: should the money be spent elsewhere?With fake likes and followers only costing a few dollars for hundreds, many businesses are giving up running campaigns and are just buying the likes directly. In the long run, this is considerably cheaper and most people won’t even notice the difference in the likes.

Regardless, the goal seems to be about artificially increasing exposure in websites, but that's not something exclusive to the rich. For example, videos go viral all the time, for something as simple like a cat yawning or something. If you have to pay millions of dollars to recreate the same success model, I would argue that's inefficiency, rather than a wealth disparity.