This is something that has bothered me for some time. For new construction, can the builder get his C of O without floor coverings?

My new-home-inspection clients tell me that they want a nicer carpet, laminate, etc. but the builder charges a premium for that upgrade. Instead, the homeowner agrees to the cheapest carpet or vinyl floor covering and then rips it out the next week.

This is wasteful and must be wrong. Is there a reference, code section or a link that supports the builder's claim?