1 million is nothing to scoff at, as that equaled over $4.8 million in sales! What’s interesting is that the average never really seemed to go too high, considering they were selling games as popular as Batman Arkham City, and Scribblenauts.
My theory is that fans were very excited, and paid the minimum for Steam keys so they could get Batman Arkham Asylum. The additional games that were later added, such as Mortal Kombat’s 3 earliest games, might have been the reason why people chose not to increase the minimum above the averages too much. If, for example, the latest Mortal Kombat game had come out instead, I could have easily seen the average shooting way up.