Heres a nifty thing from personal experience.
I bought Mass Effect 1 used, I played it and I liked it, so much so that I bought ME 2 brand new and every bit of DLC that came out.
I also bought Fallout 3 used, at the time i did not have enough cash and it was the only copy i could find, I did however purchase all of the DLC.
I understand where your argument comes from OP, but unless the developer goes bankrupt I wont feel bad, because if I bought a used copy it means someone else bought it new, and I couldnt find a new copy or digital copy.
Things arent as black and white as they seem.
I bought Mass Effect 1 used, I played it and I liked it, so much so that I bought ME 2 brand new and every bit of DLC that came out.
I also bought Fallout 3 used, at the time i did not have enough cash and it was the only copy i could find, I did however purchase all of the DLC.
I understand where your argument comes from OP, but unless the developer goes bankrupt I wont feel bad, because if I bought a used copy it means someone else bought it new, and I couldnt find a new copy or digital copy.
Things arent as black and white as they seem.