Revealing mistake: When William is running at the end, there is already a blood trail on the floor. Clearly from another take. (01:15:10)
Revealing mistake: When Eddie is cutting the stomach flesh, there is a point where if you look carefully, you can see the outline of the fake flesh. (00:03:50)
Revealing mistake: There is one shot of Simone cutting off her arm where you can see it is a fake arm. It's noticeable by the change in colour. (00:04:50)
Revealing mistake: In the opening game, the same shot of the needle moving on the scale is used twice when Eddie drops some flesh onto the scales. (00:05:25)
Revealing mistake: When Hoffman strikes the matches, he throws them in the petrol. However, if you look carefully you can see they are not lit when Hoffman throws them. (01:10:30)
Answer: The tools were chained to the tables, and there wasn't anything else they could've thrown down onto the scales.
erikvduyn