Competitive eating is not a sport. It may require extensive training but in a way that harms the body. Consuming food at a high rate of speed is extremely unhealthy. Sports are generally considered to be a competitive physical activity that requires physical training. That physical training and the activity involved in playing in a sport usually lead to better health, not worse. By that definition, competitive eating is not a sport.
Our entire global ecological system has a finite number of resources. With our global population growing exponentially, these finite resources have a dangerously close expiration date. Competitive eating is completely unnecessary. Imagine a society that would burn through excessive amounts of food for the sake of competition, but would donate $0.75 a day to help starving children around the world.