A South African supporter spotted All Blacks fullback Barrett nudging the ball with his foot while referee Nic Berry had his back turned during the 16-all draw in the Cake Tin last weekend, and posted TV footage of the incident on social media.
Feedback from fans online didn't lack heat.
Some believed Barrett should not have indulged in such gamesmanship and kept the ball at the mark where the penalty was awarded. But others asked why there wasn't a similar outcry about RG Snyman illegally entering a ruck prior to smacking into All Blacks lock Brodie Retallick and dislocating his shoulder.
Hansen, speaking at the Bledisloe Cup squad announcement in Christchurch on Wednesday, said Barrett had simply done something many goal kickers do during their careers.
"Look, you guys [media] have watched a lot of footy from club level right to the very highest level; I would say most goal kickers have done that at some point in their time," Hansen said.
"Is it right? Probably not, but they all do it.
"Is it any different than when you get a penalty and kick for touch and end up taking two strides past the mark to kick it out? It's just what happens in footy."
What now seems certain is that Barrett, who shared the kicking duties with Richie Mo'unga during the Rugby Championship test, will be under scrutiny whenever he lines up a penalty – from fans and, perhaps, referees.