You have to learn how to separate the two. It's that separation that makes it possible to control spending money after all. I mean I would 100% spend money on investments but for entertainment? Every now and then as well as a part of what I actually earn. Around 5% ish, maybe up to 10% if I really wanted something. If you really thought of gambling as an investment then I guess it's "justifiable" to spend money on it, so you do you I guess.