My 2 bits here, for what it's worth, I love STP, and I loved VR, for different reasons. Lets face it, STP would not be STP without Scott, and VR will never be VR without Scott.
I saw on the Howard Stern interview that he needs like 60K monthly just to survive, with alimony, child support and all that fun stuff, hell that's more than I make a YEAR. I'm thinking money is definitely a prime motivator here like has already been mentioned, and while some say he's selling out, the dude has bills and is going to go down the road that makes him the most money as most people would do, no?
Scott is getting older, he's past his prime, so he needs to make some wise decisions here otherwise he's going to end up another has been IMO. I love the guy, but with his past, not like he's got people breaking down his door.