given episode (or their estate, seeing as so many left us) or get special permission or something like that. ABC is cheap.
They have to pay the actors their going rate--that would include their estate--if applicable. CBS airs classic episodes of Y&R all the time. They just did so yesterday. ABC is definitely cheap and here's proof:
Sony (network of $158 billion) owns CBS.
Disney (network of $199 billion) owns ABC.
If ABC wanted to air classic episodes--they could certainly do so. I just don't think they really care about GH which is why their budget is so razor thin.
I think something bigger will come, but this was something quick they could do and was cheaper to re-air than L&L's wedding or their 1993 return episode or Bill dying in Luke's arms (that should have been the one they aired...I mean, I wish I could forget the Eckharts myself, but it would be a reminder of Anthony Geary's talents.)