What restaurant would not have a "vegetarian option" except perhaps a burger joint?

• Almost every place has salads, and always some options without chicken or eggs.
• Almost every place has breakfast option with pastries and can make any breakfast item without meat (though if you don't do eggs that will be limiting).
• Almost every Mexican place can make burritos, etc. without just rice and beans (again more limiting if you don't want cheese)

Now if the question is are there any vegan restaurants or places where there is no meat in the cooking area, well, that would be unlikely at any airport in this country.