Let me ask atheists one question. Do you believe in charity, in helping those in need of help? Do you believe in always standing for truth? Do you do your duty towards your family and your community without expecting something back from them? Do you refrain from harming other living creatures? If you do so, no matter what you say, you are following Hindu philosophy.
Perhaps what you really mean is that Hindus have adopted beliefs and practices of many atheists - not matter what the Hindus say about it.