Bank robbery is a bad example of a financial crime..

But embezzlement, etc... Are often punished harder because these are deliberate crimes, often thought-out by rational people. And these crimes are done by people to who a great responsibility was entrusted.

Most violent crimes, most crimes in fact, are not even remotely thought through. They are extremely impulsive, or unlike to be financially motivated.

Finally, crimes like corruption and embezzlement constitutes serious threats to society. Because they erodes peoples trust in institutions, rule of law, police, etc.

Americans would trust wall street more if there was fewer financial crimes..