Once there was a man named Honi. He came upon an old man planting a carob tree.

“How long does a carob tree take to produce fruit?” Honi asked.

“Seventy years,” the old man replied.

“You idiot!” cried Honi. “Why are you wasting your time planting a tree whose fruit you will never see?”

“When I was born,” replied the old man, “the world was full of carob trees, planted by the people who came before me. So I plant this, so that my descendants and their neighbors might enjoy trees, as I did.”

And he went back to planting.

AND THIS IS WHY EVERYONE PAYS FOR SOCIAL INFRASTRUCTURE.