Hi,
Well, the lion's share of those transaction fees is going to go from the companies you mentioned to Mastercard and Visa. The processors will have made $100k-$300k.
Depending on whether the Humble Bundle guys spend the transaction fees out of their cut or not, the killing will have been...
Hrrm ... Bought the cag bundle 3 on July 6, did not receive the 3 games (Maw, Foreign Legion, Guns of Icarus), opened a ticked with support, got told that it should have happened and the tech team is investigating.
Now 3 days later the same person tells me that the promotion only ran until July...