Yes, there are tons of professional gamblers worldwide, not even like an individual gambler, just some companies where you can put your money in and they assure an ROI in 'X' months. I will never put my money on unknown hands even if they are reputable ones, I don't trust in any assured ROI when we are talking about gambling and the real scores/results depend on multiple aspects where you can not control any of them. But I have some good crypto friends who are doing a lot of money with a gambling business but they even told me that no one will give you money for free, you have to assume a high risk if you want to get something back.