I could be wrong about the "value" of this, but had I not gone to Miami, I was going to try and become elite in Boston via these two places, for the sole reason that I can get sodas/snacks there, which to me is the easiest/cheapest way to do it (Neither take AmEx):
Harrison Deli
805 Harrison Ave
Boston, MA 02118
AK's Take Out & Delivery
1427 Tremont St
Boston, MA 02120
http://www.akstakeout.com/index.php
Good luck!