The list is 'top grossing'. You get there by having a high sales by dollar per unit time. They put the price up and bought the app a few times. They get 70% of what they paid back. And the app is suddenly grossing the same as a $0.99 app that's selling hundreds every minute. This launches it into the chart. Then they drop the price and real customers see it and think it's a very popular $0.99c app.