there are many upsides to retail...hard copy of disc so you don't have to download it over steam, especially great if you have 56k internet. plus it involves no credit card security issues. not that i don't trust steam. it's just that i don't trust hackers.
why not just sell if retail for 30 dollars even. i would rather pay 10 dollars extra than everyone else. but i just don't want to buy something extra along with it that i already have