I don't think new games should be put up for used game sales. Economics 101, a 2nd-hand purchase is just a change of ownership and is unproductive to the market (assuming you ignore the middlemen ie...gamestop(which i always do)). Thus, the developers aren't able to get their due reward for their tasks. However, as most game sales are usually within the initial sales period(whatever they may be), I feel its okay to buy discounted/pre-owned games after the said period.

Another example is like how you purchase a 2nd hand car, Although you get it cheaper, its probably manufactured years ago but the game is printed like just 1 week ago and getting it used for a 5 dollar discount? I'd rather just buy a new one (of course unless you can get it REALLY cheaply).

Which brings me to my last suggestion. New games should be scented. Like that new car smell we love/hate, opening a box should just give you a whiff of flowers or something and it dissipate immeadiately into the air (thus this should counter all the stories i hear about people buying repackage games as new). Well thats all folks.