Are you sure of your spelling with 'li'? A pilcher was a maker or seller of fur garments. In addition, a pilcher was a now-obsolete name given to a thief, which doesn't really sound like a job-title, I must admit! A plitcher might have been based on the verb 'plitch', meaning 'to pluck'. Accordingly, a plitcher might comceivably have been employed to pluck poultry, I suppose.