Nothing wrong with gambling, gambling can be wrong when gambler get addiction and can't control their self, do every ways to still gambling and use all their money only for gambling didn't care about anything again, all in their mind is only gambling gambling and gambling.
It's not about how much you gamble or how you can afford to lose, it's about the habit you get when you get addicted to gambling even if you gamble with the money you can afford to lose, the effect of addiction on your life will be bad and will get worse if it continues it will ruin your life no matter how rich you are.
Then, we can consider that 'gambling' is wrong in the first place.
If there is no gambling, no one will fall into this black hole of addiction.
Yes, who get addicted could blamed as well as they can't control themselves to avoid too much losses and ruin their life.
So, both of them are wrong, whether the house or gamblers.