u sell it to a willing buyer, he/she/they own it & it belongs to them & the owners have the right to sell/share/keep or do anything with it.

why are you saying that people who PAID you for your work & they own it & they are NOT allowed to share it or distribute them as per GNU ?

But you are allowed to sell them freely on the other hand ? imo, i don't think your work is being stolen at all.

confused . . .