IDOS has event insurance that covers the events that IDOS sponsors such as the WCCO and Spring Gathering/Convention. We don't have the resources or legal authority to cover all the events, demos, DOGs and cookoffs of individual chapters.
From what I'm told from the insurance agents, the main reason for the insurance coverage is that we serve food and our food is ingested by other people who could get sick if we don't follow health code etc. The general premises of insurance is to have "care and custody" of the exposure.
Also, each state is regulated by it's own set of laws and rules regarding insurance. And each state can be vastly different in how, why, and what of insurance.
Our insurance is about $1000/year for 4 events.