Don't blame airlines in the US, blame airline customers.
Personally, I like the nickel-and-dime scheme, as you call it. I rarely take cross country flights. My typical travel is 3-4 hours of flying at the most. I absolutely prefer a cheaper base ticket price, because I don't care if they give me crappy food for "free" in that time frame. At 6'2", I fit comfortably even in Spirit's closely-spaced seating. I travel very light and typically have a single bag.
For me, a lower base fare with extra charges for the rest is something I prefer. I am very happy that the US air-traveling market agrees with me and has pushed the industry in this direction.