Shame is an undervalued quality. Only humans have shame, as they alone recognize when their actions have fallen short. A person who acts immorally without shame has lost the most precious of human qualities: conscience. People who routinely espouse a philosophy of "no regrets" are simply attempting to suppress their humanity and liberate themselves from morality, guilt and consequences.
Good luck with that.
Nonetheless, shame was once a central element of punishment. From schoolboys wearing dunce caps to throwing someone in the stocks and the literary scarlet letter, punishments have long relied upon public humiliation as a means of personal rehabilitation and general deterrence - and often as a bit of good old fashion vengeance.
The state has generally lost the power to employ humiliation as a sentencing device - cruel and unusual, apparently. So it's interesting to read that private citizens have offered precisely this punishment as an alternative to prosecution. There is currently an 18 year-old would-be-shoplifter dressed as a Sesame Street character carrying a sign that reads, "I got caught shoplifting at Halloween Express." I'm rather comfortable with people offering private substitutions to would-be criminals - they can always choose the courts, but have the option to give the victim and others concerned with the crime a first say in restitution.
On the other hand, a guy in Houston was sentenced to spend every weekend for the next six years pacing a busy highway with a sign reading, "I am a thief. I stole $250,000 from the Harris County crime victim's fund. Daniel Mireles." His wife is currently serving a sentence for theft, as well - their home has a court mandate sign in the front yard reading, "The occupants of this residence are convicted thieves. They stole $250,000 from the Harris County Crime Victim's fund. Signed, Judge Kevin Fine."
Maybe there's hope yet for humiliation.