Gambling isn't drugs, both of them are different. People are use drugs because they want to escape from the reality for a while or don't want to be tired if they have so many activities to do, while gambling is the purpose is to get fun, but there's many people only to chase winning and make them become addicts. How you can sure your children wouldn't drugs even though you're already gave him good advice? you can't know what your children will do after he get older and especially he met a toxic friend.
I don't how weird comparison we can make like seriously drugs and gambling can be same? Based on addiction we can't make this useless comparison because drugs can finish your life and cause damage to your health even if you take them once and gambling is for entertainment purposes from which you can have chance of winning but what does drugs offer in return? Your life shortening? They are entirely different things and drugs is worst scenario in which you should ever fall and avoid it completely in my opinion.
there is one thing for sure. - parent would not teach kids anything that would destroy their live. But on the other hand they would portray a different picture in front of them - the bad home environment can be one of the reasons they can choose a different and difficult track for their life.