Yes, these are bonuses for trades the referred users are performing. Take it with a grain of salt though. The premium was 50% initially and has been reduced to 20% some time ago.

If you have an account there, go to the account page and click on the related banner, there you will find a link. If anybody uses that to register, you will receive commissions for any trade.

Right now there are over 7 Mio. Users on Binance, so still some potential here I assume.​

Btw. if you have no account yet, clicking on a link in above post will guide you to binance. I will also be happy to assist ;-)