It is a great fact that gambling is not the main factor of people's unhappiness as in some countries the governments make it seem, but it must also be admitted that gambling is easily addictive because of its nature which is possible with very lucky to earn a lot of money putting little money, as on the internet, on tv and even in the real world people have heard stories of people who bought lottery tickets and won millions of US dollars, makes this type of stories a form of motivation for many people, although in my opinion it shouldn't be like that
but it is a fact that alcoholic beverages, which are in large quantities anywhere, are one of the biggest problems that have created many people addicted to alcoholic beverages, but like many breweries, the owners are people linked to governments, so there is no mention of this danger of alcohol, but as in the case of online gambling, there are no government people connected to online casinos, so governments take tough measures against online casinos, that is, laws work for some and not for others, so society creates a bad image about gambling and especially when they are online
I would say that gambling and alcohol being available in a society has little to do with the degree of happiness in that society.
For example, we can see at those countries which are thought to be the happiest on the planets: Denmark, Sweden, Ireland, etc. Those are democratic countries and Republics where people have the freedom to drink alcohol and also to gamble, so I do not think there is a direct correlation between both things.
The true unhappiness I would say, comes from the inability of the population to earn money working on the profession they chose, and desperation makes then turn into gambling and alcohol. There are too many social and economical factors to keep in mind when touching this topic.