Why atheism always has a burden of proof

[Airyaman]

Scientist A: "Blargoxium is the newest element, I have discovered it"
Scientist B: "I will now find evidence to deny this".

^^ When does this ever happen in reality? Rather, its

Scientist A: "Blargoxium is the newest element, I have discovered it"
Scientist B: "Interesting. What information do you have to support your claim?"

Actually, the discussion is more like this:

Scientist A: "I have discovered the newest element Blargoxium!"
Scientist B: "You have provided insufficient proof of your discovery! I do not believe Blargoxium exists!"
Scientist A: "What is sufficient proof?"
Scientist B: "No idea! Whatever proof you bring, is insufficient!"

I was talking about the methodology that is typically employed to show something is real or has been discovered. If you want to talk about god, particularly the major ones, its like this:

Scientist A: "Blargoxium is the newest element, I have discovered it"
Scientist B: "Interesting. What information do you have to support your claim?"
Scientist A: "I have this book that says it exists. More than one person wrote in this book, therefore it must be real!"
Scientist B: "OK, have fun with that, I have more serious endeavors to occupy my time."