This actually just reminded me of something that occurred yesterday or so. I was attempting to try out the DSGameMaker against my stronger sense and I could not make heads or tails of what I was doing and somehow it screwed up on me and wouldn't compile anything anymore. Funnily enough, the regular example stuff from PAlib made more sense...I must be crazy xD.
In any case, I think there is no point in spending the time to make something, especially a game, if you don't plan to have others play it (what is so great about playing it by yourself anyways xD) it kind of defeats the purpose. Selling a piece of homebrew...dunno about that really. I mean if it was a really legitimate game (like full on unique system and fun, etc.) I guess it would be fine to charge a dollar or so and have a demo, although I think it would be better to just have a donate button.