The remaining 1% are those who are making a living from gambling.
That's means gambling industry are so rich because they take the 99% chance of making money compared to only 1% of their gamblers who make a living in gambling. I don't know what percentage exactly but I do believe it's possible to make a living in gambling and 1% is just too small, maybe like 5%, but like I said, I really don't know because I myself is not making a living in gambling although in the past I tried to find ways to make it possible, but failed.
Its hard to determine the rate, but it's easy to determine who really are making profit in gambling, and it's non other than the gambling operators.
Aiming to make gambling as a living is a hard job, maybe the hardest kind of job in this world as we know that majority of the gamblers loses over time.
If we have enough capital, maybe the easiest way to make a living in gambling is just to start our own casino or gambling sites.
Its very difficult to make a casino yourself. There is an opportunity to invest in an already functioning gaming site. And there are actually a lot of such sites that want to attract investors for their business. One such site is Mintdice
But I am not familiar with the details of investing.