Yes, this is a correct statement. And now ?
I think everyone will agree
Well, you can't speak for everyone. Moreover, you can't even assume that everyone is going to agree with this statement in the first place
Ever gambled on the street? This topic has everything to do with how things are going to pan out there. And you are in for a big surprise if you expect "a zero-sum game" there. It is also called "learning it the hard way". Can anything be more practical and realistic?
I never gambled on the street, no, sorry
I gambled, like a lot. Lost as much, due to a failure to see and understand how things work in practice and for trusting other people a way too much. Remember that climax moment from Interstellar (probably worth watching the whole movie)?
Please give an example how such a "street game" would look for you with all the parameters and what you would expect the result to be
Does coin tossing count?
If it counts, then you can start out with the example presented in the OP. A simple setup, known for literally millennia. You have 100 dollars and I have 100 dollars, the base bet is 1 dollar. Someone has to bust and relatively fast at that. Pretty much a "street game" if you ask me, and nowhere near a "zero-sum game" (as you mean it), Certainly worth trying it out with your friends, to feel it with your skin in the game, so to speak
As long as your bankroll is finite, the staked amount is not zero, and remains the same (e.g. 1 dollar), on an infinitely long timeframe you will either bust or win provided the same terms are honored by your opponent too.
Is all this a realistic scenario? No. Players that are in profit will leave the game before it ends. Now you will say: but, street rules. Yes, street rules, but no sane person will play against you
To begin with, no sane person will gamble on the street. Yes, I was basically insane back in the day to gamble on the street if this is what you want to hear. But I was young, stupid and stubborn as youths can sometimes be. You can't leave while in profit unless the other side agrees or you have agreed beforehand upon the time when it is allowed to take dough and run. Indeed, if you could force your way out you would, but no one would be playing with you again