Probably that explains why so many people were playing dice on Freebitco.in despite the fact that there were lots of casinos with a 1% house edge.
Well, that explains it in part. Some people prefer to gamble at a casino with a higher House Edge (HE) if it offers better software, better customer service, or better promotions, for example.
We shouldn't forget that, in the case of FBI, there were several factors that reduced the HE, such as having sats deposited there, holding Fun tokens, or having a high betting level. But, after all, other sites offer similar deals, like MetaWin with their NFTs, for example.