I didn't even know there was a gmail contact list, but after looking around I found it. There is no site on earth I can think of that would be relevant for all

I didn't even know there was a gmail contact list, but after looking around I found it. There is no site on earth I can think of that would be relevant for all of my contacts which as everything from work-related, product related, friends, past friends and random people I don't even know. I will only assume that this is the case for most people. And with that I struggle to see anyone using this button, care to elaborate? Maybe I am the only one that never looked at his contact list before.