It is worth noting that the meals at the HSMP are not stated to be "pilgrims' meals". Though many pilgrims stay at the HSMP in the pilgrims' rooms on the top floor, there are many more rooms for non-pilgrims on the floors below – though there is nothing to stop pilgrims staying in one of those rooms if they want to pay a little bit more. I would say that the meals at the HSMP are usually better than the "menú peregrino" or "menú del día" served in restaurants along the caminos.
A menu del dia is far better than a pilgrims menu
It is meant for workers to have a decent hot meal during the day . Millions of workers in Spain and Portugal use it every workday of the week during mid day and it consists of a starter, a hot maincourse and a dessert.
And important , it costs between 10 and 12 €
It was introduced by the former Spanish dictator generalíssimo Franco and still being served in almost every restaurant
So you are far better off to buy a menu del dia than a pilgrims menu what most of the time consists of a burger, french fries and some lettuce .
In San Martin Pineiro they served small portions as we Dutch have the expression “ too much to die and too little to live on” and when I was there last year 12 € for a menu what was every two or three days the same dish .
I prefered the Italian or an Asian restaurant in Santiago rather than this San Martin Pineiro one.