Crooks had his apple box over his bunk, and in it a range of medicine bottles, both for himself and for the horses. There were cans of saddle soap and a drippy can of tar with its paint brush sticking over the edge. And scattered about the floor were a number of personal possessions; for, being alone, Crooks could leave his things about, and being a stable buck and a cripple, he was more permanent than the other men, and he had accumulated more possessions than he could carry on his back.(Steinbeck 104)
He also does not seem to mind having horse stuff around him so he probably feels like his job is permanent in some ways.
Since he is stuck in a permanent situation he has things messy since he doesnt have to worry about leaving.
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