They can absolutely vary in size, however proportion/conformation is vital to their ability as working dogs. It has nothing to do with show.
I’d like to know what type of work a ‘pocket pit’ is bred to do?
It seems to me that people are breeding for a certain look/fad, rather than for a specific job. Responsible breeders breed for excellent conformation, and stable, correct temperaments, working titles and clean health.
Obviously this dog’s job is to be a pet, and I have no doubt that it excels at that job. What is unfortunate about fad breeding is the fallout seen in shelters across the country.
Sorry for the rant. Back to the original subject, a kong with peanut butter frozen in the freezer works wonders and will keep them busy for a good while.