Most people create other accounts for bad purposes like collusion, bonus abusing or to not comply with certain restrictions applied on his account, so there is definitely a risk that you won't get paid of you are caught.
That's a pretty bad thing to do because playing gambling just to chase the bonuses offered will potentially have bad consequences for the main account. I think it's better to play professionally or if they think their main account has no luck then they can deactivate it and create a new account. But I don't know if such actions will be dangerous or not because the IP will come from the same device.
As far as we know, gambling requires luck, sometimes they are frustrated with the main account because They have made many deposits but have never felt victory. So they will create a new account to seek luck, but it can be interpreted that it will be a cheating if they do not deactivate their main account.
Gambling should not exceed the purpose of fun and excitement because it has the potentials of making people to regret ever going into it due to the fact that it can be addictive if not checked properly.
Infact anyone opening multiple accounts on any casino for what ever reason is already addicted because I don't see the reason why anyone will be thinking of opening multiple accounts on the same casino .