Of course if they had known it would have fallen to $5, they would have waited. Anyone would have. But nobody has the fortune to invest with 20/20 hindsight
ALso, 500M is a lot of money but it's not THAT much money when you're running a multi-billion dollar company and responsible for delivering billions in revenue. To get those numbers you have to invest in things. NBC isn't sitting around wondering if they can eek out another million dollars of ad buys for the TODAY show this quarter.