Gambling is not legal in many countries. Cryptocurrencies provide anonymity and thus it is convenient for many people to use it. At the same time cryptos like doge coins and tron are very cheap, using them to gamble does not burn the pockets. Gambling website that accepts crypto do not need KYC which means you are completely anonymous.
Yup this is right in my country gambling is not legal thats one reason why I use crypto gambling site to play online casino games.
Another reason the transaction fee was too small plus less hasle and easy to use all you need is good internet and fund to your account some popular gambling site also offer a contest, bonuses and exciting suprises.