"In our view, any publisher that disables used gaming risks a backlash or boycott of its titles by gamers, negatively impacting sales," he said.
Describing potential activation fees, Pachter said these are similarly unlikely.
"They would face a huge backlash" he said. "They wanted manufacturers to do the dirty work, and both refused."
According to Pachter, GameStop stands to be hurt the most not from the impact of potential used games restrictions, but the recent revelation that Xbox One games will be available digitally on day-one.
"We believe that this disclosure has the greatest potential to negatively impact GameStops business, as GameStop is unlikely to participate directly in these digital sales," he said.
At the same time, though, Pachter said it is in the best interests of Microsoft and publishers to integrate GameStop's PowerUp Rewards currency into digital transactions in some manner, thus giving the retailer a cut.