I only ever buy treats in the dogfood section
GSD stomachs tend to be a bit finicky so they get fed a home made food (I do a big pot every 7 days with 2.5kg of chicken, 1kg rice and half kg of chicken livers) then mix it with rusk just before feeding. Unlike dog food they never get bored of it.. Supplement that with veggie and other food leftovers and they have a more balanced diet than I do!!!