In this case it could be the first time it was used for real. However, I do not have the data for it so it is just a hunch and because I know them. They were the biggest at the time when dice websites first started out to be off-chain, before that it was satoshidice but they were on-chain and nowhere to be found now. And ever since those days, they grew bigger and bigger and bigger. Then came in Stake and they used all that information and experience into making this the biggest. Now they have partnerships with Watford, UFC, an important fighter in UFC, and now Drake as well. Maybe they are not the biggest, or maybe they are, I do not know, but they are %100 up there fighting for the top spot very clearly, even if people think they are not the biggest, nobody can deny that they veeeery close to it. This is all in "crypto casino" world of course, there are real life casinos with tens of billions of dollars in profit, thats not what I am talking about.