Why do we load passengers in the airplane from the front back in US?

Deplaning, makes perfect sense but I started wondering why do we load the plane from the front rather than the back? You'd have all the overhead storage being used back to front so if you run out you can easily start checking bags at that point and you know everything to the back of the plane is full. You also have all the people sitting in the back having to brush passed all the passengers already seated, if you loaded back to front this is not a worry. Once the plane lands the ones that got on last get to leave first so it's much more equitable.

I have a feeling the answer is just greed but just thought I'd see if there was another reason.