Open carry of a handgun without a permit is legal in Nevada. Advocates now sometimes carry deliberately to test reaction by Los Vegas police and to demonstrate their constitutional rights. Police sometimes stop and search them, then return the gun when they determine it has been registered.
Our gun laws are a crazy quilt, just like our drugs laws. In some states, possession of small amounts of marijuana is still a felony while in places like Humboldt County, CA, it is de facto legal. Our gun laws are equally all over the map. Why is open carry legal in Vegas but a serious felony in New York City?
In Vermont, concealed carry without a permit has been legal for years. There have been no crazed gun rampages there to my knowledge.