I read a fascinating fable as a kid. This was probably 1974-1979. I do not remember the title or author (sorry).
I remember all the details of the plot as I was blown away (remember, I was an impressionable boy!) by the shocking conclusion. Here goes: Two brothers go into the desert to seek their fortune. They come upon a kingdom where everyone wails in grief. They discover the favorite princess is locked in a tall tower and everyone fears she will die there. The brothers are presented before the king and one brother asks, “Do you have a key to this tower.” The king says, “Yes, but I don’t see what good that will do.” The brother requests this key. The two brothers go to the tower, use the key, unlock the door, and the princess is freed! The kingdom rejoices! The king presents each brother with a chest of gold, which they carry into the desert, onward to seek their fortunes.

They arrive at the second kingdom. Terrible dehydration is killing everyone there. One of the brothers asks the king, “Do you have a well? A bucket? A rope?” The king answers, Yes, to all those questions but adds, “I don’t see what good that will do.” The brothers are tight-lipped as to their plan. As one might guess, they tie the rope to the bucket, lower it into the well, and bring up water for all in the kingdom. The kingdom is saved! The king gives each brother a chest of gold.

The story continues this way, the brothers solving what seem to be easily-solvable problems for each kingdom, each time acquiring another chest of gold. After they have each acquired seven or eight chest of gold, they stagger into the desert one more time. Soon, one of the brothers drops dead under the weight of his treasures. His brother is sad but collects all the treasure chests in addition to his own treasure chests and tries to stagger forward. He only gets a few paces before he too succumbs to the weight, has a heart attack, and dies.

A man with a camel finds them, dead in the desert and says something to the effect of, “These two are idiots. If they had only spent a piece or two of gold, they could have bought donkeys to carry all this gold. They wouldn’t have died.”

As a boy, I was stunned that the two main characters died. I was also stunned by the simplicity of the solution to their problem and how I hadn’t thought of it, while I was busy looking down on the idiots in each kingdom, unable to solve their own problems.

I’d really like to see this story again. Made a big impact on me.