It's definitely some weird logic to assume that people wouldn't want Scrooge. I mean, I get it...it'd be a figure of an old man in his night clothes...not something the average collector is clamoring for. At the same time, they've made Marley and the Ghost of Christmas Past, with the plan to make Christmas Present and Christmas Future at some point...they all appear TO SCROOGE! Old man in a nightgown wouldn't sell if that is who they started with, but that isn't the case here. At the point that they finish the ghosts, all those who have invested in this set will want Ebeneezer to complete the core cast. I cannot imagine anyone who has bought all four ghosts just saying "naw, don't need Scrooge...he isn't that important". I'd completely understand if this was a character like Tiny Tim they were expressing doubts about, but it's literally the MAIN FREAKING CHARACTER!
If they are REALLY that concerned about it, do a two pack of the final ghost and Scrooge. The Ghost of Christmas Future is usually depicted as a Grim Reaper type of figure anyway, and we know they have plenty of parts to make that without spending a dime on new tooling. If anything THAT ghost is the one that collectors might skip buying because they can cobble together what they need to make him from existing figures, so pack him and Scrooge together and call it a day!