Demoulas Market Basket. Proudly non union.
I mentioned today to my sister that the employees of Market Basket (and I've been to several) seem so much more cheerful than workers at Stop & Shop (also been to several of these). She told me that Market Basket employees (in addition to being non-union) get profit-sharing! No wonder Stop & Shop employees seem relatively glum -- no profit-sharing and getting soaked for union dues! ;-)
Ding! Ding! We have a correct diagnosis!