Give mine a bowl of only purina and you will have the proof that dogs do remember AND compare !!!!!
They will scatter the purina all over the place.
Of course give them only purina a couple of days in a row and they will finally eat...... out of hunger.
Children are no different----
Brussel sprouts are a good example
I can remember stuffing them in my cheeks to spit out later
Otherwise, they appeared on my next plate- breakfast.... that was always the threat !!