Walmart is not the place to get oil filters anymore IMO. You only have a choice between Fram and ecore, and I'm not sure which is a lesser of two evils lol. At least Kmart carries Purolator. AA and AZ have Purolator/Bosch and non-Ecore Delcos and Napa has WIX.
AcDelco filters are still available in non ecore versions but Walmart just wants to carry the cheaper ecores. Also they probably don't want to carry the pf52 because it's not as common as the pf47 now. And maybe ACdelco wants to provided the pf52 in the Classic design. That's too bad though because the pf52 can work in place of the pf47 and you have a longer filter.