Personally, I believe that if a person spends no more than $100 a month on gambling is the first sign that he does not have a gambling addiction and is quite able to control their budget. It happens that I spend $200 on gambling but I always split this amount into two different deposits and do not allow myself to spend more than $100 per day.
I think that is way too much unless your monthly income is $10k+.
You shouldn't allocate more than 5% of your income to gambling. You should treat it as an expense because you are mathematically guaranteed to lose it all given that you play with the funds for long enough.
Would you spend $200 a month on movie tickets?
Probably not.
Have the right mindset.
$100 or $200 may not be too much for some people.
However, gambling addiction cannot only be measured by how much you spend every day or every month on gambling, it is also measured on how frequent you gamble.
Usually, a person will never know when he's addicted or not, because we always believe that we gamble normally even If it means that we don't have time for different thing other than our day jobs or business.
I would also add that it is not only about the money you use for gambling, but also time! Imagine you have under control that you only gamble with $200 at maximum every single month. But you go back and forth with winning losing, spending one third of your lifetime gambling. Are you addicted or not?
Time is a very important variable I think that should definitely be considered. There are many other things in life that could suffer from being neglected no matter how much or less you spend on gambling. Or take your mood: let's say you lose $200 in a day and are done for the month, is everything cool with your inner mood? Are you the same person on that day or are you frustrated? What if you are frustrated that day and people get to feel your frustration because you are able to control your budget, but not your mood? There are a couple of angles that must be considered as part of this discussion in my opinion.