Hm, I could have swore I told this forum to notify me if I had an answer .. *glares at forum software*
Anyway, I can understand the wish to be notified, I also like to hear about it when somebody uses my stuff
It's just that formally asking for authorisation can slow things down, because you can't do anything else while you wait for an answer.
For example, if I'm writing an article on volcanoes, I'll prefer just to find
appropriate images under a creative commons license (and then drop the photographer a line "hey, I've used your pictures here !" - though it's not compulsory), then better images where I have to ask permission.
Of course, the main advantage of Creative Commons is that if you're kidnapped by space aliens or communists and tortured to death, people can still reuse your tiles in creative ways without having to wait 75 years or so (And I'm not sure my great grandchildren will fully appreciate all the work that was put into 32-by-32 pixel art)
(That said, I didn't put any of my work under Creative Commons until I started encouraging other people to do the same ^^)
By the way, the game I'm making is called
DreamStones, but for now only uses the ten or so tiles I drew myself :-P
(And no I'm not a door-to-door insurance salesman in real life ^^)
Cheers !
Emile