Scratches and superfectas

[analyizethis]

I've noticed that recently at NYRA tracks, after the scratches, superfectas have been added to the betting menu of races.

This seems like a recent change and is a little problematic as the past performance pages, programs or other documents would not note that exotic opportunity but more generally; what is the rule and the logic behind it? I am a little confused because I thought that superfectas were excluded based on the number of betting interest and unless both entries are scratched and two entries/betting interest draw into a field you never have more betting interests after the scratches than before and you usually have fewer.