The hairiness of a hobbit's foot, his lack of shoes, the bright colors he wears and the pipe-weed he smokes are not very relevant to the War of the Ring. But mentioning it in the very beginning certainly helps to set the scene.
A few small details are enough to generate immersion. The fact that you believe they were lower middle class in spite of the fact that he didn't mention it suggests you created a mental picture. I did too - in my mind the man was black, white t-shirt, a bit of grease on it. That's how the mind works, and writers exploit it.
A blue collar worker is lower class by definition. As phrased above, the "tall and muscular" bit is part of the writer's observation/stereotype that the man is a blue collar worker. "He was big and strong and (therefore) looked like someone who works in manual labour".