You might be surprised how often they do turn-up at the shelters. Many people get puppies, but by around 4-6 months if they don’t know how to handle and train the breed they get dumped at the shelter. Sadly, due to the poor work of the original owners these dogs often have severe behavior issues on many fronts. Poor socialization, illness, poor vet care, and on and on.
Someone offered a 1 month old Malinois. I almost took it, but I realized I work too much and wouldn’t be able to train it like it would need to be.