As per my original comment, these examples are only indicative that profitable endeavors can come out of these things in unexpected ways, but that's not the point of doing these things. I'm never going to profit from, nor recoup the costs I've sunk into most of the mad science I do. That's not the point. I do it because it's fun and because I like building cool things.

These examples are one justification for why we should embrace these kinds of hobbies, and not the desirable outcome for these kinds of hobbies.