Really not that suprising that the F6 did a lot of ground/surface work. It may've been designed and made it's name as a fighter but towards the end of the war, it became more of an Attack Bird. Couple of reasons this happened.
1. Fewer dive bombers were brought aboard as the Kamikaze threat grew. Why bring on a plane that only bombs (SB2c) when you can bring on one that bombs and dogfights/defends the carrier (F6F).
2. As the Japanese airforces became less of a threat, the job of the F6s to escort dropped off. So, send them along with bombs and rockets on board. Only a short step from that point to getting rid of the birds they were escorting altogether.
3. F4U became the fighter bird towards 1945 with the F6 going more to Attack work.
4. Japan's economy is based on a lot of inter-island sea traffic. Small ships of less than 1000 tons. Sinking them would've been right in the F6Fs wheelhouse. Search and destroy runs up the coast.
5. Ground attack during the Okinawa and Iwo Jima campaign went to anything that could carry a bomb. F4F, F6F, TBM, SB2C, all of them did a lot of work in that realm. It was what was needed so they did it.
The F6 was a do anything kind of bird. Was somewhat suprised it didn't survive to fly in Korea. It really had the right qualifications for the job.