^Indeed, the episodes available for streaming on Netflix sometimes have material cut out -- specifically movie clips whose rights must have lapsed. Not sure if that's true for the DVDs as well. But it gets awkward sometimes when the setup for the myth is explained by the movie clips. In that one about using a harpoon and blasting caps to blow up a shark, it just jumps to the team starting to test the myth without any prior exposition of what they're testing.
In cases like that, it seems it would've been a good idea to produce alternate, animated exposition sequences, like the ones they use to recreate movie scenes they don't have the rights to. Then they'd have backups in case their license to the actual clips expired.