The Magpies fined Swan for the Footy Show interview on Channel 9, where he denied he had an illicit drug problem.
"Our players know the rules and Dane and his management didn't follow the rules - it's pretty simple," Buckley said.
"It was a no-brainer.
"If you don't follow the expectations and needs and demands of the footy club, you cop your whack and you move on.
"It's not a huge issue, but five grand is not a sniff of money.
"I dare say Swanny would understand he couldn't do it the same way the next time."
But Buckley said it did not detract from Swan's strong pre-season.
Swan was rested from Saturday's match and Buckley said the side for the Brisbane game was picked three weeks ago.
"It doesn't take away (from) any of the positives we're seeing from a football perspective (with Swan)," Buckley said.