What is an Artist?

As I was devouring my sub in my favourite food outlet of choice, subway. And before you ask, the regular choice is 6 inch honey oat with tuna and extra sweetcorn!
I was somewhat confused by the idea of the title of the workers in the fore mentioned franchise. They are not simply, chefs, assistants, servers, no no they are classed as sub artists. At first i found this rather amusing how could someone who creates an item of fast food be considered an artist? But then it lead me to question what is an artist, and who can be termed as such?

We see our "work of art" created in front of us and we get to make the decisions in the process, which filling? cheese and toasted? which veg? and lastly which sauce? So in a sense is unique to us, or own mini masterpiece, as in theory no sandwich will be the same, our own edible masterpiece. With such customer participation in the process does this then make us the artist?
But maybe i am thinking to deeply?!
Next time you enter your local subway will you treat your food as an edible artwork? or is such a title a mere fad, an attention devise, aiming to make your sub seem unachievable to create by our mortal hands!! Although some might question the function of some art, such as Dadaism, its main aim is still as an artwork whereas a subway sandwich is not unique/shocking/meaningful. it is ultimately just a edible object, with one ultimate aim consumption.