Some pups/adults will not accept treats outside of the house. Cant say why, just works like that sometimes. I know if they're anxious or fearful, they'll sometimes deny a treat but that's not always the case. Sounds like your pup just enjoys the praise and knowing she's doing good.
Shasta GSD 5/5/10 CGC, ITD, TC
"Dax" Thor z vom Weberhaus BCAT CAX2 CGCA ETD HCT NCO-1 PKD-T RATI RATN RA TC TKA 3/18/2013
"Hades" Guilty vom Blutfeuer 10/26/2018
Zena GSD 6/1/03-2/16/2016
Riley GSD/BC 1/10/05-2/1/2013