Your question contains a problematic assumption. To ask “Why do religious obligations lead to financial fraud?” suggests that religion itself produces corruption. In fact, this is a misleading link, because religion and human behavior must be separated.
Religion as principle – True religion, especially the Abrahamic faiths, consistently calls for honesty, virtue, mercy, charity, and helping the poor. These values are fixed and noble.
The human self – Human beings are not perfect. They carry desires, ambitions, weaknesses, and influences from their environment. These factors may push some toward dishonesty or, conversely, toward righteousness.
Actions vs. values – Fraud and corruption arise from human misuse, not from the essence of religion. When people act dishonestly while invoking religion, this reflects their personal failure, not a flaw in religious obligations themselves.
So, the correct way to frame the issue is not that religious obligations lead to fraud, but that some individuals exploit religious obligations to cover their weaknesses or greed. The responsibility lies with human behavior, not with religion.
One might as well ask why the love of money leads to financial fraud. There is no clear connection between religious obligation, love of money and financial fraud other than that in today's world, all three quite often involve money.
I find the question problematic. to me, there is no direct correlation between religion and financial fraud. Any organization, sacred or secular, are run by infallible - and sometimes malicious - human beings. Religion is not unique in this regard.
I would be curious as to why you made this assumption in your question.