Yes, but in most cases it was only the camera[person] and us viewers that saw the "Diesel" marking on the inside of the lid. That was likely well anticipated by the producers, as a way to add a bit more challenge to the land-only [well, sea too] treck this week.

As for Vancouver, it would be hard to keep a secret like this shoot from the media. I suspect that is why so little is shot in Canada or the US, except for the start and ending. The remaining teams have a lot of Africa and Asia to get through before hitting NAmerica -- think this was episode 5 or 6, of a 13-episode series -- but could be hitting the continent via YVR.