I see it the same way. It is probably quite easy to register this way, since the checks to ensure that the data is basically valid (and not stolen) are probably not as thorough as, for example, when opening a bank account.
However, it definitely becomes problematic when you want to withdraw a (larger) amount. They will definitely take a closer look and if a stolen identity is discovered, the funds will be frozen and you will never see your coins again. Therefore, if you want to use Roobet, you should enter your real data, which saves a lot of time and trouble in the future.
The type of people who use fake accounts are rarely the people who would win a lot of money and withdraw, they are small time gamblers who are trying to win a small amount or get the benefits of the competitions and bonuses etc etc. I feel like if you can actually get a proper fake account from a proper place then you can probably just defend it as well so I am not sure if that would be an issue.
What is the issue is that there is someone out there who has no idea his ID is used and he looks like he is gambling, he could get in trouble with law if he is caught doing it while he himself is not doing it at all. I know a person who had this problem, someone stole KYC information of an exchange and used his KYC information to gamble and he was put in jail for 2 nights and then had a court case, he provided his IP which did not match the IP of the gambler so he was let go, but it is still 2 nights in jail because of this. Fake KYC should be prevented no matter what, even if it doesn't hurt Roobet, it hurts others.