By Elliot Gulliver-Needham UK high street shops like Sainsbury’s, Marks & Spencer and JD Sports are facing a shareholder backlash after failing to commit to pay all their staff and third-party contractors a real living wage. Big financial names backing a campaign against low pay include LGIM, HSBC Asset Management, Aviva, and Scottish Widows. In total, the institutions have a total of $6.6 trillion (£5.2 trillion) in assets under management. The campaign is being led by responsible investment group Shareaction, who plan to push back against a variety of retailers over their wages throughout th…