My own co-workers (at least one) have stolen out of my duffle bag at work. People steal from each other all the time. I’m sure people have stolen from you and continue to steal from you, it’s just different forms of theivery. Do I think stealing is wrong yes? But if someone robs a bank for some reason like money for food I have no qualms.
If someone robs me at gunpoint for my car I wouldn’t feel bad. It’s the society we live in. I don’t know what put it in your mind that I would steal from people now.
I was thinking more about this question...I think it is likely true that consequences rendered by some group are always ever-present so how could I truly say what I would do without such a threat of consequence.
But it seems that religion only takes the question to a "higher" level and people find their way to justify murder on down for God.
The trick with our free will is to establish habits which divert us from situations which tempt us to do wrong even if others do so. True, the fact of being a victim is a strong inducement to do the same and one often has little control over the environment in which they must make their moral choices.
Also moral choices are often complex as an act of theft might yield a good such as feeding one's family when no other recourse is available. In that context moral laws falter, hence why we have judges, humans who apply some measure of oversight to the robotic and inevitably limited value of moral laws.
So I guess, speaking to the OP, it is probably necessary to have some sort of "higher power" whether civil or faith based in order to have the sufficient desire to raise one's moral fortitude above average. This requires a lifelong self-awareness of forming habits and cultivating an empathy with others such that you and the others are equals. This is the basis, IMO, for individual moral development.