That logic applies to pretty much everything nowadays. Books, CDs, DVDs, Games, etc. Why investing money in releasing something that will be online the next day? Filming the Concert for the Philippines, mixing it, editing it, and putting on a DVD also costs money and they'll probably include it in the CD/DVD version of THP, knowing that a HD version of the concert is already online. I don't think releasing a making of DVD would have hurt, considering they probably have hundreds of hours of the recording process.