I can't imagine myself "playing for fun". In my opinion, the pleasures in the game are very clearly associated with winning. And if there are no wins, for me, continuing to play becomes a problem. And even a series of losses makes or would make me think about continuing to play. I can only repeat that I do not get pleasure from losses. But if you play just for fun, then losses are just part of your game. Most likely, even a long series of losses will not be considered a "streak of bad luck". The same thing happens when you play for research purposes. Since your losses are small and controllable in amount, there is no point in doing anything special after a long series of "failures".
So you mean you gamble just for fun. If that's the case, then I'll ask you two questions. I hope you'll answer these two questions.
My first question is, if you gamble just for fun, are you affected by the outcome of the game?
The second question is, when you gamble, don't you feel like you have to win your bet?
If you're not affected by the outcome or if you don't care about winning or losing, then I'd say you gamble just for fun. But from my experience, I can at least say that no one gambles for fun, and everyone who gambles for money expects to win.