I was more refering to the point where Aurther and Ford made up a point, so they could eat the berries. And most of these people who do stupid thing either never think they will be caught, or they won't be punished if they are. They are quite willing to believe anything, so long as it gets them what they want; damn the consequences later.

So the idea of the poison wasn't much 'doing it safely', but that would rather come up with some lame excuse why they had to do it. Most of the time it involves you being pissed at them; sometimes it backfires and they are the ones who end up pissed. But no matter what they odds, the majority are going to come up with the excuse to do what they want.