A butter substitute?
This line may refer back to the previous stanza—asking whiter the substitutes (a staple, a champagne flute) are actually better alternatives
It also refers to mundane butter subs like I Can’t Believe it’s not Butter!
Lerner expands these gestures, that ask the reader to imply connections between disconnected phrases, in his third book Mean Free Path, c.f.:
I organized, distributed fliers like
goes out to all
My people were
Possible worlds, encouraging
from “Doppler Elegies”
To help improve the meaning of these lyrics, visit "[What, if not the derivative, will keep us warm?]" by Ben Lerner and leave a comment on the lyrics box