The ovals are wrong. (And could give a better idea if they were rectangles.) The Beck rally crowd looks larger, for sure, when you actually look at the photos and how the crowd extents correspond to the map.
Just a note: Libs on other sites are pointing out that the ovals are wrong (they are), and also saying that the two sites’ maps are on different scales (they aren’t, as it is one single photo).
I took me about 3 minutes to create and post the graphic in question. It more than made my day that Libs heads were exploding all across America. :-)