Egotistical is the wrong word perhaps, but it's an absolutely degenerate trap to accept, and a path to personal destruction if continually embraced. You'll have little to no authentic substance as a human if everything you do is predicated on how you'll make money from it, but only in situations where realistically it's a choice. People who get into this trap end up as amorphous blobs or empty husks. People need things in their life that they do for the sake of it first, with money coming as an ancillary benefit if at all.
I've only spent money in the last year (no earned income), laid off a year ago, and I'm grateful to have saved enough to last some of the drought of work. I have to be careful to modulate how much I'm spending, but if I didn't, I'd be wildly worse off now that had I not at all. Spend as frugally as necessary, but have some hobbies or passtimes that you do just for you, selling the result if you like, but don't predicate your participation upon whether it's valuable to anyone else.
In the US, or many other developing countries (i.e., those without a robust social security mechanism), the only way most of us can afford to pursue our passions to a high degree of performance is through cross-subsidization with a "real job".
The benefits that passion provide to a rounded life, better mental health, sense of perspective and so on are far worth the price paid, assuming your day job can finance it appropriately.
It's either that or poverty, which works OK for some until they have or want a family, get sick, have to take care of their parents or worse.
Monetizing passion is a shitty Faustian Bargain imposed upon us by the time and place we live in, unfortunately.
What you may be getting at is that somebody who is being creative as a job should be fairly paid for their work. Which I totally agree with, but I don’t think that’s what we’re talking about.