I was also thinking that perhaps that might have been a reason. Though perhaps it's odd that MGM/UA didn't do the same for hoDS:
And the interesting thing is that once the opening credits for NoDS become their widest, the credits are no longer boxed:
And though I could see MGM/UA doing the boxing for the closing credits of NoDS because those credits are much more widely spaced than the closing credits for hoDS are:
Even without boxing on the Blu-Ray, the black space to the left and right of the credits doesn't seem all that much wider on the VHS than it currently is on the Blu-Ray:
Who knows?