Theoretically casino bets are more risky than the sport betting. In a dice game the probability of getting a number is very less than what happened in sport betting. And also in a casino game there is a house edge which you can not defeat. But in sport betting there is no such things.
If there is a house edge that means casino's can win in the long run so it's risky to us.
However, in sports gambling if we are not good in selecting odds then that would not prevent on taking big risk as well, we might also lose in the long run so we have to be smart in looking for value such as odds like 100+ or those odds with over 2.00.