I think part of the reason they used the express pass is they couldn't figure the canoe out. Yeah no one was there yet but if they got half way out and everyone was getting there they wouldn't have the option to use the express pass and leave. So not the smartest use but not the dumbest either.
As for the snowboarders I would have run for it too. It is a race. The snowboarders aren't even really a super strong team in comparison to the others physically. I mean they have won a ton of legs but many of them were because some other team did something stupid. So I definitely don't think the teams are really uneven. (If you want to see a race like that see if you can find the first season of expedition impossible where the same team won all but one leg of the race... and only lost that one because of a twisted ankle during the foot race.)
As for the snowboarders I would have run for it too. It is a race. The snowboarders aren't even really a super strong team in comparison to the others physically. I mean they have won a ton of legs but many of them were because some other team did something stupid. So I definitely don't think the teams are really uneven. (If you want to see a race like that see if you can find the first season of expedition impossible where the same team won all but one leg of the race... and only lost that one because of a twisted ankle during the foot race.)