Well, if people would prefer physical discs over digital distribution and would insist of having a proof of ownership, I guess Sony wouldn't have a choice but to prefer physical distribution.
But since customers don't care, who else should care?
I always prefered physical disks. That was my #1 pro-console argument. Without those disks, I simply won't buy anything console related. I vote with my wallet, simple as that.
Of course I know that people will still buy digital disks and then cry when Sony will do something unthinkable like revoking access, but I guess that won't be my problem.