Wether you invest or not you still cant make a profit in the long run. It is still a gambling even you invest and no one can win the long run in gambling.
Your investing on the house and the house won't lose in the long run unless someones cheating every roll.
So your likely saying that its a guaranteed profit if you invest in the house since house wont lose in the long run(your just a part, you dont own the house and its different imo). Then how could others keep struggling on earning bitcoin? Why others choose to play instead of investing? Remember dude, the word "gambling" is still there. Invest or nah it is still a gambling.
Every investment has its own risk. There is no such things as 100% profit. If there is, ton of people would have flocked and the % would be so low that it is almost insignificant. And that is what bank do. However, it is wrong to say investment is gambling, cause gambling is only happen when you blindly invest and never do any research. If you do your own research well, you can profit from it most of the time.