I wasn't arguing that part. Obviously if something is no longer being sold then your only option would be to buy used or find someone who has an unwrapped game for a decent price. Plus, in my case, I want games that are older than the last generation so they have no use for me there.
It does affect developers and publishers just not as bad as other industries. And like Stealth pointed out, they have voiced there opinions. They would rather have you not do it, but again since it's not as bad as other industries they don't really push consumers to buying new, because they still do it anyways. People buy new just as much as people buy used so it balances itself in the end, since you can't have used games until someone buys them in the first place.
From the past figures that Gamestop put out, it seems they are making more money than some developers and personally I'd rather have that money go to the developers than Gamestop. I would rather support them and have them make more games.