For example, atheists have agreed that it is IMPOSSIBLE to prove God doesn't exist.
The existence of a Christian god is unfalsifiable. That much is true. Much like the concept of Bantu, the Supreme Cosmic Toad from whose flatulence the universe came into existence, is unfalsifiable. However, specific claims made in the Bible can be falsified. And have been falsified by modern science. Like the age of the earth, the origin of life and humans, the Noachian flood, and so on. Since so much of what the Bible claims is demonstrably wrong, this leaves us no reason to believe the other claims in the Bible that cannot be falsified.
So, since it's impossible to prove God does not exist, atheism is based on faith, not facts, not logic, not reason, just pure and simple faith.
Atheists don't believe in gods because no convincing evidence of the existence of gods has been presented. So the atheists's lack of belief is based on sound and practical epistemological principles. Can you explain why atheists should believe in gods when no evidence can be presented?