Related for Bava Metzia 178:12

Workers that were hoeing among the fig trees or picking dates or harvesting olives -- they may eat and are exempt, since the Torah gave them permission (see Deut. 23:25-26). [But] they may not dip [the figs or olives] in salt and eat unless the homeowner gave them permission, and they may not eat them with bread unless the the homeowner gave them permission.