The first line of this news story says:
Call it space grave robbery for a cause: imagine scavenging defunct communication satellites for their valuable parts and recycling them to build brand new ones for cheap.
I've heard people use that "for cheap" construction before, but thought it was dialectal (mid-to-northern English). I was surprised to see it in an NZ publication.
Why does that almost pass grammatical muster, whereas "for expensive" (for example) really stinks?