Convenience store chain 7-Eleven said Monday that it is recruiting 20,000 workers for its 9,000-plus U.S. stores. The company and its franchisees have already added about 50,000 workers since March. Classified as an essential retailer, 7-Eleven has been operating all year, adding its mobile checkout technology to new markets, expanding delivery to another 400 stores and putting in-store pickup in place at more than 300 U.S. stores. The new hires will help 7-Eleven manage the surge of mobile orders. The Consumer Staples Select Sector SPDR ETF undefined has edged down 0.6% for the year to date while the S&P 500 index undefined is up 0.1% for the period.