Actually, many fast-food places DO have vegetarian selections!! Anything without meat is vegetarian, isn't it?
McD and the King are exceptions to the rule!
Taco Bell has many things without meat (bean burrito, cheese quesadilla, etc). When I go there, I encounter many customers that also order their tacos, burritos, and other "regular items" with beans instead of meat. One even ordered the Mexican Pizza with beans instead of meat!
Panera Bread offers vegetarian sandwiches and soup, as well as salad (pick two for only $6.49)
Chipotle, Qdoba, and Baja Fresh all offer vegetarian versions of everything that has meat!
At breakfast time (in the fast-food places that have breakfast), you can get egg and cheese with no meat!!!!