When it comes to abusing bonuses by registering multiple accounts from the same household, the approach should be quite simple, but not as simple as locking all accounts.
First of all, when I worked in a casino, we usually let the first account remain open since it's not the player's fault that that someone else registers in the same casino from the same household. The player often doesn't even know.
Secondly, it's good to look at the point whether the other accounts really misused the bonuses or not. The patterns are often very clear. The new account always uses the first deposit bonus, maybe another one, loses and never logs in again while another account is created, the bonus is used and then it repeats over and over again. Then it's clear it's just 1 person playing on multiple accounts and misusing the great bonuses for new players.
But I've seen numerous cases where let's say a husband played in a casino for a few months, used a bonus from time to time, did many deposits, his account was verified. Then he told his wife about the casino and she registered there. She may used the first deposit bonus, but in some cases, she didn't even use it, did a few deposits without a bonus, verified her account and once she won, her account was closed for "multiple accounts" and winnings voided.
That doesn't make any sense since it clearly shows there are 2 different people using their own accounts and having a standard player's behaviour - that means: play, deposit, lose, win, sometimes take a bonus when it's available. That's why we generally don't agree with closing accounts and voiding winnings for "multiple accounts" reason, especially when the only evidence is the same IP address. It's necessary to look at the cases individually. And trust me, I know that most of multiple account cases are really just 1 person creating multiple accounts and that's it.
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