Bonding of CSST is for protection from lightning strikes in the area of the building and NOT anything to do with the wiring in the building. This has caused much confusion.
To reduce incidents of failure the manufacturer of CSST requires the gas piping be bonded where it enters the building with a bond wire, based on the size of the service or as specified by an electrical engineer.
This was all decided by lawyers NOT electricians.
As a disclaimer they also specify that in areas prone to lightning strike the building should have a lightning protection system. Lawyers again.
In Indiana CSST is not allowed to be mounted within 2 inches of any metal including duct work, water heaters and furnaces.
On one job the electrician explained the bond wire would be an extra. The service was 3,000 amp and the gas pipe was on the other side of the building. The mechanical contractor replaced the CSST with black iron. Pipe is a lot cheaper than copper wire.
Failure to bond puts the liability on the contractor instead of on the manufacturer of the CSST. There is one pipe clamp UL listed for use on the hex fitting of the CSST connector, but it should be the last choice for the bond connection. Best point of connection is on the iron pipe where it enters the building.
