How do you guys spot scam betting sites ? Which are the red flags with those kind of sites and do you believe the rating/review sites or they are mainly paid like the ICO review sites ?
A little google search can save you from scam betting sites. If you come across a cryptocurrency betting website and you want to know about the reputation of that website, try finding its thread in bitcointalk forum. See if the thread is active and if the old members are rating it well. That is when you know the difference.
Always a simple way to go, most especially if it is a cryptocurrency gambling site. One way or the other, someone must have talked about the site's reputation. Asides that, I would rather focus more on sites with reputation and do more research on that than trying to find an unknown gambling site that is not being used by so many. When there is a red flag to any website, the hand writing will be all over the wall but as long as people have tried it and it has been running for years without issues, what else would someone be looking for?