On Thursday, he repeated his claim that he is now far more relaxed in F1.
Button, who was not close friends with Hamilton over the past three seasons and often clashed with the brasher Briton, said in Melbourne that he was "very, very surprised to hear" Hamilton's criticism.
"The freedom I have in this team is phenomenal," he insisted.
"It's so not like that," said Button, referring to Hamilton's description.
"It's a very open team, free team, and a team that will do anything for you."
According to a report in the Associated Press, the difference between McLaren and Mercedes is that the German carmaker can partly fund its team with mass road car sales.
Button agreed: "In this team, you work, you have to work, and perhaps harder than in other teams.
"Initially when I came to the team, it was a shock. You learn to understand, to adapt -- that is the job."