Khesrau Behroz did an amazing podcast about those operations (in German though) [0]. Basically when there was a crack down on providers of illegal sports betting in China, they went abroad and diversified. The betting operation is used to launder the money from those scam operations and betting is still immensely popular in China and done via VPN. Those East Asian sport betting providers are sponsors of many Champions League clubs so their (often changing) names get know the gamblers in China watching the games.
So yea, there are massive amounts of money involved.