concierge vs street sweeper

concierge

noun
  • One who attends to the maintenance of a building and provides services to its tenants and visitors. 

  • One who attends to the wishes of hotel guests. 

street sweeper

noun
  • A person who is employed to sweep streets, pavements, and gutters, keeping them clear of litter. 

  • A machine used to sweep streets. 

How often have the words concierge and street sweeper occurred in a corpus of books? (source: Google Ngram Viewer )