Physical Danger
There is a certain amount of physical danger associated with camp counseling. If you're hiking through the forest and you see a mama grizzly, yes, that's dangerous. You're also not making it through the summer without at least one ball hitting you in the face.
While you may be worried about taking a soccer ball to the dome, you need to be primarily concerned with the safety of your campers. One of your main jobs as a counselor is helping to keep kids safe, and yes, dangers abound at camp.
If you're supervising swimming, it's probably safe to assume that you know how to swim and you're not at any risk of drowning. But seven-year-old Johnny might not have your skills, and you need to be constantly aware of where he is in the water.
Luckily for you, you're probably not going at it alone. Counselors are usually partnered up, and there's always older staff there in case things get hairy. But if you're supervising physical activities—sports, hiking, swimming, archery, and others—there's a very real risk that kids can injure themselves. You'll need to have a handle on first aid, and have the numbers for the local authorities on speed dial.