Good point, but in the end you messed it up - studies show that the availability of pornography reduces the number of sex crimes. It turns out that this serves as a relevant replacement.This will not work in gambling - compare your emotions from, for example, losing (or winning) a million fake dollars and real ones. I think the difference is huge.
Playing with fake money doesn't give any sensation even if we gamble with a lot or a little bet, it's the same because we won't feel happy about it.