Consider the following scenario:
Imagine that there were two people let us consider them as A and B. User A works at night and used to use superuser at night. User B works at day and used to use superuser at day
Now as per the community rules if user A gets blocked with his account then obviously user B can't access his/her superuser account due to their IP
And the users A and B may like to cheat superuser by voting each others. So why can't we allow only one user per i.p?