Yeah, I wouldn't have minded Morrison but Santana has been much better, overall, and much more OBP-minded his whole career, even though he is older. If I was a GM I wouldn't want to pay big money to someone who put up Freddy Galvis offense as recently as 2015 either. So the question is if Morrison can keep doing what he did last year, based on changing his approach. And obviously nobody was willing to answer that question "yes" with a bigger/longer deal.
And Santana is also a switch-hitter.
Of course who even thought the Phillies needed a 1B? Pre-Santana I thought Morrison would have been a good, if luxurious, 1B/LF bench piece, though not a platoon match for Williams.