There are different types of gamblers depending on what they play. Some gamblers are rounded and play all kinds of types possible but there are those who only stick with one type.
For example, one could just play slots while one just sports betting. My question would be which one do you think is more addicting? Slot machines are more rapid and you can play it more consecutively because it is fast unlike sports betting where matches take time. You might get addicted on sports betting more if you enjoy analyzing things and winning it might give you some pride for your skills. Not to mention that if you are a fan of the sport you are betting on, surely you are emotionally invested in the sport therefore would want to follow it and bet on it many times.
Now, what is more addicting? Slots or sports betting?
It's not about the game, it's about the individual that loves the game. There are some gamblers that doesn't like casino games. It's not like they don't want to play it but they are very bad at using it, so you see that it will be very difficult for casino games to be addicted to such kind of games, but if you really like the game and you know how to play the game you will likely be addicted to it and same goes for sport betting, it's all you know and understand.
If money isn't involved, some people might be really addicted to some of these things but it's affection for money that makes people learn this gambling and since they are used to it, the addiction becomes permanently whether you are making money from them or losing money from them. It doesn't mean that because you know how to play slot or sport betting you wouldn't be addicted, you can even if you don't make loss and similarly when you lose too much as well.