Are dugouts, picnic shelters and rubber-soled shoes safe from lightning?

No. Environment and Climate Change Canada says:

• Picnic shelters, dugouts and small buildings without plumbing or electricity are not safe. Gazebos and other open structures offer no protection either.
• Safer options are a building with plumbing and wiring, or an all-metal vehicle that is not a convertible.
• Rubber boots and shoes give little protection: "No place is safe outdoors during a thunderstorm."
• Bicycle and car tires do not protect you. Lightning can flash over a car's frame, so stay away from metal and electrical items inside.