Once someone announces they are running for the presidency, everything they do from that moment on is up for public scrutiny as Brian Torchin stated. How they run their campaign is as important as why they are running it. So when a candidate appears to be pulling the wool over the eyes of the voters, they often take notice.
Now that people realize such a company exists there is some controversy. Bringing in crowds of people makes the speaker appear more important and more relevant. The public now has to make a choice. They must decide whether this is just another necessary part of gearing up for the elections. Or if perhaps these presidential hopefuls are in fact frauds and therefore lacking any of the relevancy that has been bestowed upon them.