In the pre-modem era, the sale of surplus food took place once a week when farmers took wares on market day, into the local village marketplace. Here food was sold to grocers for sale in their local shop for purchase by local consumers.

第3句 Here food was sold to grocers for sale in their local shop for purchase by local consumers.中Here是状语，谓语是 was sold to，宾语是 grocers，for purchase by local consumers是主语food的主语补足语，in their local shop是地点状语，那么for sale做什么成分？