The food industry in general is full of low wage jobs and this isn't restricted to "fast food"...I'd venture to say that most of the restaurants that have been mentioned here as favorites are staffed with lower wage employees, even in the kitchen...It's been my experience that the old saying "You get what you pay for" is usually true...If restaurant owners aren't willing sacrifice margin to pay more for quality, it usually ends up in the product(the food in this case) somewhere down the line...
I've heard that a good indicator of restaurant kitchen cleanliness is indicated in the condition of it's restrooms...Restrooms in poor shape indicate kitchens in poor shape and vice versa....
Just some "food for thought"...