Disk sports are worthwhile, but we have a Sports merit badge plus Athletics, Golf, Snow Sports, Water Sports. There's no pressing need to fragment sports further.
Disc Golf should be incorporated as an alternative requirement to Golf MB. We already do this with Snow Sports and Skating MBs. Most schools today use Disc Golf as a part of their PE program and schools are starting to install courses due to the low costs of maintenance and the ease of use. The schools certainly do not utilize regular golf as a curriculum addition except as a High School sport.