My Russian friends say that no one says "nazdrovye" when drinking together, but it's in all the films. Why?

Hello, you are probably a bit wrong about pronunciation, usually at the feast, russian people says "za zdorovye" not an "na zdorovye". The difference between that two sentences is when russian people says "na zdorovye" they want to show their gratitude for gratitude. "Na zdorovye" means "You're welcome".

Example:
— Can you give me a glass please, I want to pour vodka.

*Apply glass*

— Spasibo!

— Na zdorovye!

So, let's talk about "za zdorovye". This is the usual toast, which says Russian people. Actually thats looks pretty strange because "za zdorovye" means "I want to propose a toast to health and prosperity". I mean alcohol negatively affects the health, how can we drink for it? But this is absolutely normal in Russia and no one gives it value. :)