Crib dates from the mid 17th C. and refers to provisions. It is standard English and correctly refers to a container for animal food. Its use was first noted in Australia in late 19th C. when it refered to a snack or light meal.
Snap is interesting. It is at least 16th C. and means to share food. However, it later came to mean the process of sharing criminal booty, particularly from pick-pocketing and similar street crime.
Bait is from old or middle English (beyten) and means to bite.
Scran dates from the 18th C. Originally it was the payment for food at an inn but evolved to refer to bits of food, left-overs and "broken victuals". Scran is an old Royal Navy term for rations. A scran bag is military jargon for a haversack.