This is a story about money. This is a story about being frugal. This is a story about raising your baby brother.
As you can imagine, money was tight for the Winchester's growing up. Yet, Sam never wanted for much. This is not because John and Dean spoiled Sam rotten, although they did, but because Dean gave when there was nothing else left to give. While Dean went to bed most nights hungry, Sam was full. Dean would never allow his brother to starve. Dean wore threadbare shirts and ripped jeans and had old sneakers with no traction left. Sam, on the other hand, had comfortable, new clothes every time he asked for them. Dean would not let the kids in school judge Sam for something he had no control over. Every September, Dean took Sam out to get new shoes. Dean made sure the ones he bought Sam were comfortable and durable even though Sam would outgrow them soon enough. As soon as Sam complained about his shoes being too small, Dean would have to go out and buy him another pair. Dean took care of Sam in every way a little boy needed. He was a friend, a brother, a father, and a mother all wrapped up into one little Dean. Sam never wanted much as a child because his big brother, Dean, always gave him everything he needed. So, yes, Dean may have appeared frugal, but that is only because he was saving his money, waiting for his brother to ask for something. This way, Sam will never know how destitute they really were. If Dean handled his money well, Sam would never need to worry; and that is all that Dean ever wanted.