It's all about the reaction, like when they go back into the toilet as thought the next time they try leaving it'll be back in the right place.
I wouldn't be too shocked if this was staged - moving the set around would be noisy and probably take longer than it takes a dude to pee, plus nobody worked out the huge object next to the toilet in the middle of nowhere is part of the gag. Finally, if they accidentally caught gang stalking man he would probably have snapped, torn his shirt off and gone on a spree, screaming at people and generally getting locked up.