Did competitors think the maze vines are deadly?

The stupid thing is that Cedric would have been alive had Harry not try to "save" him from the vines that just spit them outside the maze.

The movie leans towards Harry thinking the vines are deadly.

Shouldn't they have been told before going in "Oh by the way, don't worry about your fellow human beings being swallowed up by vines, they'll be fine"? What kinda lunatic would go for a trophy instead of helping? Well besides Draco.

If Harry did think the vines kill them, he considered letting Cedric die just so he could win a meaningless trophy for one year. What the hell?

Seems this trial of "letting your fellow man die so you win a trophy" is something Voldemort would come up with.