If someone's turned over a new leaf and hasn't committed any infractions on this new account, then we have to ask ourselves: is putting a permanent stain on their IP going too far? It's communicating that you're so odious we think you'll never change and those in your household will also be the same.
How do you know that? (And/or how do you know the multi-account history of the people using the accounts?)
Some might also be caught up in IP-address-based bans, but for accounts like this I expect there’s a reason they remain banned.