Like some others here, I’d have to say my roadfood influence was just the neighborhood around me as I was growing up. In my case, it was a suburb of Washington, DC with a substantial Jewish population. My family was not Jewish and my mom was a classic meat and potatoes goyishe cook. Nothing special–or very interesting. So I’d look forward to "roadfood" meals at delis and restuarants in the area: not only delifood, but sub sandwiches (sooo much better than Subway), archetypal pizza (made by a guy who sampled the real thing in Naples during WWII, came home and opened a restaurant in which he tried to duplicate it), the forerunner of the Big Mac at a place called Topp’s which was the first independent car-hop burger joint in the DC "burbs" (at least the first one I experienced), and all kinds of seafood on trips around the Chesapeake and to Ocean City in the summer.
Then I went to school in Baltimore. As a single student away from home for the first time, I was "forced" to sample the divine roast beef sub at "the B&M" (a little place in the basement of a row house), the etherial hamburger sub at Harry Little’s (Baltimoron alert!–is it still there?), more fantastic Kosher in East Baltimore, luscious sauerbraten at Hausner’s, Italian soulfood at more little holes in the wall in East Baltimore and all that the North Avenue and Lexington Markets had to offer (a lot of what we now call artisan foods).
Finally, I went south to grad school in N. Carolina and grew aquainted with pulled pork, grits and all manor of vegetables fresh out of the summer garden. By this time I think it’s fair to say I was in love with all manor of "roadfood" and I still am.