I honestly had a hard time making a decision on this one. First I thought 1 life for 1 life and I get richer (positive sum). However I realized it is the equivalent of killing someone for organ traffic, which is immoral. I did not put the lever.
Or maybe how rich he was, because I think some people had the instinct to choose via "eat the rich" philosophy (fair). But if the question was just "if you run over one you inexplicably get $500,000" the answers would be different, I think.
If it was $10 people might be more inclined to accept because that seems like a less immoral amount of money somehow. Like, $500,000 seems very Serious but if it's like "you will run over the same amount of people but also can buy yourself a snack afterwards" it feels Ok
Please do add various rewards options and randomise them. With 600k observations you are going to have a pretty good experimental paper despite the convenience sample.