Could you elaborate? Who pays for what exactly?

I am kinda triggered by that comment because you make it look like it's easy or inexpensive. It's not.

I also came to Germany with just a suitcase and a backpack. I paid for my tickets, paid for mandatory health insurance that covered timeframe before I started my job, paid my rent, paid government for processing/issuing my residence permit, etc. I've paid taxes and health insurance every single month since then, haven't used any unemployment benefits once, took a single sick leave.

You might argue that I "stole a job", "worsened housing crisis", or something along these lines. But there are plenty of data points that disprove majority of such arguments.