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.
Absolutely right, if you are good in internet browsing and searching you can easily find and gather material about the doubtful betting sites.
To search about it in popular forums like this one is best practice, i usually do the same for finding anything related to cryptocurrencies.
the best solution is to find reviews of gambling sites that we want to use .. because it will be very important .. especially if we will gamble using large funds .. because if we choose the wrong place to gamble .. instead of pleasure and benefit we can .. but lost all the funds we have