It’s everywhere. All age groups from middle age downwards (not heard in older people yet). My child’s teachers (primary and secondary), presenters on tv and radio, my kids trying to adopt it from their mates. Not cockney or accent related (ie like a Nottingham accent that does replace th with f a lot), just pan regional sloppy speech that seems to have caught on. I fink, I fort, bruvver, uvver. Why?