you do not have to wear goggles, but don't you dare try to hold anyone responsible if you get jammed in the eye.
FYI, if people who play do not sign waivers acknowledging the possibility of injury and making Fandemonium and the Nampa Civic Center not liable, then yes, people can "dare" hold Fandemonium and the Nampa Civic Center responsible. If, after the waiver has been signed, people then choose to go into the game without protective gear, then they wouldn't be able to blame anyone else for their injuries (within reason).