It's not as if they spring the GPL licence only after you use the code, though. It's more like "hi there, if you want to use my code, these are the terms under

It's not as if they spring the GPL licence only after you use the code, though. It's more like "hi there, if you want to use my code, these are the terms under which I've made it available" than "you used my code, now play fair".