I guess there may have been maybe a handful of people who might have traded or gambled huge amounts of bitcoin in the earliest days, which at the peak could have translated into hundreds of millions if they had whale size wallets. Beyond that, no gambling sites even come close to these numbers when you're talking about single winners. Lotteries have possibly the biggest user base and are accessible in so many different markets that it's impossible to compete at that scale. You are best off looking for a lottery that is applicable to the specific country that you reside in, as that will reduce any potential complications when it comes to claiming a win and you don't want to find out you're ineligible at that point.