During a “fireside hangout” on Google+ on Thursday, President Obama told one questioner he doesn’t know why “people” haven’t gotten rid of pennies.

“Almost all economists agree we should stop minting pennies,” John Green, of Indiana, told Obama. “They’re economically inefficient they don’t work as currency… we’re talking about maybe savings to the federal government of 100 million dollars over  ten years, but it’s also really obvious. So my question to you is, why haven’t we done it?”

“I gotta tell you, John, I don’t know,” the president answered.

“It’s one of those things where I think people get attached emotionally to the way things have been,” he added, reminiscing about piggy banks and trading pennies in for dollars. “Maybe that’s the reason why people haven’t gotten around to it.”

Obama then took the opportunity to use the penny as a metaphor, blaming Congress for not passing “efficient” legislation he has pushed, such as consolidating business-related agencies within the government.

“Any time we’re spending more money on something that people don’t actually use, that’s an example of something we should probably change,” he said. “And one of the things that you see chronically in government is its very hard to get rid of things that don’t work, so that we can then then invest in the things that do, and the penny ends up being, I think, a good metaphor for some of the larger problems that we’ve got.”