Human morals/behavior aren't like a fractal that's the same at every level. Let's see a study like this where much larger amounts are in play.

As a young adult, my dad warned me that people are basically honorable up to about $10K. In practice, I've found everyone's threshold is different and fluctuates greatly with their individual situation and the broader economic situation. For example, right now I'm seeing otherwise successful and decent folks do really ugly things over 4 figure money.