i think its difficult to say that one bitcoin casinos is a scam if that site is new site but we only know by reviews from other people about the site and from that reviews, if something bad happen we can avoid to play in that sites. but i think there is a sites that have big list bitcoin casino that already scam people. for the old site, there is no guarantee to them if in any case, they scam people and run away with the people's money. but in my opinion, to know that one site is getting scam is by making a withdraw but the process could take a longer than usual and if we asked them, they will said its normal process and i think this is a sign that the site is getting scam and we need to be careful with this.