The risk is that you will have a substandard roof installed, missing vital components; all because the roofer did not take the time to identify missing items and supplement the insurance company for them. The roofer who does not file a supplement is usually not a quality roofer and is in the business for a quick buck. Cutting corners in roofing almost inevitably will result in roof leaks within a couple of years after the roof is replaced. That's not what should happen with a new roof!