I remember working in a restaurant many years ago, where it was part of new hire training to demonstrate the importance of salt and pepper to a burger's taste. We would make 3 burgers, one no seasoning, one poorly seasoned, and one properly seasoned to the spec, and then we would taste test them all. The difference in taste was so night and day I was shocked the first time I participated in the test. Yeah I guess you don't technically need salt and spices, but not adding them or using just a pinch is not the same thing at all.