Smart or Picky Eater?

Grandson's dog, Nemo, WON'T eat baloney/balogna, weiners, expensive dog food, canned dog food, pickles, brown/rye bread, dog treats, restaurant gravy, but he CHOWS OUT on cheap dry dog food, IF slewed with leftover bits:  crock pot stew, carrots, potatoes, homemade gravy, ham, bacon, beef, chicken, turkey... errrr...everything else...7th heaven for him:  moose/beef bones/ frozen leftovers.