Every big company that is involved in financial matters purchases all the domains in their name so that there is no phishing attack.
where did you get this info from? there are more than 1k TLDs, it would be impossible to buy them all, not to mention how much it will cost to manage and renew each year.
they do buy a few, but only the popular ones if they could or have a trademark for the name.
Because if a domain falls into the hands of a scammer, he can do a lot of scams with it and at the same time he can steal a lot of money from that company by selling that domain to them. There are many such incidents where if a company forgets to purchase one of their domains, then they have to buy it later for a lot of money. And since a lot of money is transacted in online casinos, the issues in these cases are even more sensitive.
or they buy the domain, forget to renew it (or lose it for some reason), it gets dropped, and a scammer gets it anyway.
you can find many examples of this if you do a quick online search.
Interesting... anyone facing this when claiming from the box?

just tried claiming and i got the same error.