Disagree. I have never seen a situation where a game developer was able to reasonably suggest that the presence of used games on the market seriously cut into their sales. 80%-90% of the time major developers rely on the first month on the market, hype, and reviews to get their sales. They are not interested or focused on the gamer who buys 3-4 games a year and only buys them 3-4 months down the line after the price has dropped, which is really when you start to see used games on the shelves.
Secondly, most people who go into a store and purchase a used game do not go into that store with the purpose of buying that game. They do it because they happen to see it, they've heard good things, and it's much cheaper. Publishers like to think that every used game sold means that they lost a sale, when in fact it's the opposite. People who buy used games would have never bought them in the first place had the game not been sitting on a shelf for $15 instead of $45.
Not only that but I think you could make the argument that used games sales help a series get on it's feet. I would've never bought The Witcher 2 if not for seeing it for around $20 and picking it up on a whim (that DEFINITELY wouldn't have happened if it was still retail price of $45-$50 dollars). But because I bought it, and loved it, I know that CD Project Red is an awesome developer, and I will be picking up The Witcher 3 on day one.
tl;dr I think the concept of major publishers like EA and Activision (who are the only publishers really pushing this) losing massive sales to used-games is a marketplace fiction.
