Its hardly a suckers game if you know what you are doing. I know prop traders that make huge bank essentially daytrading on the forex and others.
Sure, its highly controlled gambling, but you of all people should realize that its not a losing game for everyone. If anything, its just a suckers game for small timers -- like all other gambling.
Any sufficiently volatile form of gambling has big winners. That doesn't mean it's +EV. The markets (especially forex, from what I hear) are such that even if it were impossible to outperform the broader indexes, you could very well know multiple people who did so over a period of years or even decades.
See Fooled by Randomness for a more detailed explanation.
if you open 1 lot in your life and sell it and outperform the market, yes that's random. If you open more lots and your success rate is higher than 50% then you can't really call it random. Playing random in forex kills you.
You can win more than 50% of wagers even over fairly large numbers if you're -EV, especially if you're only slightly so and the variance is large. And with tens of millions of people attempting to do this between forex, stocks, futures, etc., it's a virtual certainty that one could find a large number who have.