I find this so strange. Growing up in NJ we always knew these sandwiches as subs or submarine sandwiches. But, when we were in NH for the summer, they were called grinders. Now, if you do a Google search on "grinders" and add almost any Lakes Region town name, you get "0" results. Use "subs" and all the local favorites show up. I don't think it's Mass residents that have taken over in NH, it's Jerseyites.