Ariely study

I am curious about  Ariely's study in chapter 12. He is curious as to how people are more likely to steal/cheat when it's an item other than cash. 

If I were to develop an experiment to see if people were more likely to steal products rather than cash I would have cash available and another product like candy. Leave it in a room where the subject can take it at anytime without being seen and then after one day, 3 days and a week and see how much is gone at each time period. This will show that if a person has more time to be tempted would they be likely to steal the money too?