Rattlesnakes aren't really that scary. The ones around Georgian Bay (The Massasauga Rattler) don't get too huge and only have a striking distance of about 1.5 feet when they're full grown. They also can regulate the flow of venom once they're full grown so only about 25% of bites actually get a full dose, and its really the immature ones that you need to worry about.
I worked at a provincial park up there and saw snakes all the time. Researchers often came up to tag them and measure them and stuff. What actually worries me is how small the bucket was that they put them in. Anyway, while rattlers are certainly potentially dangerous, the chances of having bad issues with them are relatively slim, even when handling them.
PS I don't know what kind of rattler that was in the video and only half watched.