Bread Soul cafe is a quiet, friendly spot with lots of pre made veg options to take out or eat at one of their sidewalk tables : salads, hummus, lentil or veg soup, veg sandwiches on whole grain bread. The prices are reasonable for Manhattan and the location is key--a few short blocks from Lincoln Center, Lincoln Plaza cinema and Central Park. This is a commercial area with few veg-friendly or inexpensive places nearby. The servers are efficient and they understand if customers want to eliminate dairy or other items from a menu choice.
And for your sweets-loving companions, there's an ice-cream stand on the same block. Both sell coffees, muffins and other quick snack items.
Cons: Limited seating