The main purpose on here is to prevent casino players cheating on their end, that's why the system closely monitored this kind of activities. Duplicate accounts can be detected through their respective ip being used everytime they logged in, and they're very strict on this matter because everybody is very clever on this matter trying to beat the system but always fails.
Casino business always one step ahead so, much better if we play fair to avoid future circumstances and our online account will be safe from possible ban or suspension.