I assume scalpers are often much better at getting through a heavily contested purchase flow (eg the recent steam controller release) due to tools like bots, general experience, and being able to dedicate 20 minutes or more to sitting at a computer constantly refreshing a browser window.
This way it's just a random draw and (I think?) the number of accounts scalpers can enter with is limited because they need to be established. So it might not solve scalping, but it could be a significant improvement.