They actually cover these concerns, acknowledge it was a problem with examples of siblings or students behind a shared IP, and then developed a parallel cookie based tracking system, using the "server welcome message" which is served as a web page in the in-game browser.
It's also worth noting this is a 3rd party dedicated server provider, who manages and leases community run game servers. Getting a ban here would prevent you from playing on that provider's servers, but not any of the official matchmaking ones or servers from another hosting provider.
It's also worth noting this is a 3rd party dedicated server provider, who manages and leases community run game servers. Getting a ban here would prevent you from playing on that provider's servers, but not any of the official matchmaking ones or servers from another hosting provider.