The food rating here really depends on who is eating. The "meat-eaters" in our group say that the burger is of very high quality and one of the best. The "gluten-free-eater" in our group is really happy that there is a bun-less burger with a lettuce wrap.
The low rating is influenced by the vegetarian view: The veggie burger is nothing to write home about, the bread is quite soggy and tasteless. And while there is a nice variety of veggies, they miss some spice or herbs.
But well, this is probably not a place targeting vegetarians... ;)