"We pinch pennies elsewhere, but it's worth every dime to pay a living wage," Ocasio-Cortez said.
Willie Rennie, leader of the Scottish Liberal Democrats, said the company should be "ashamed."
'In the birthplace of John Lennon, it falls to us to inspire people to imagine,' Shadow Chancellor told Labour conference.
Self-employment accounts for almost half the jobs created since 2010.
Campaign group Amazon Anonymous are encouraging shoppers to have an Amazon-free Chrismas