question:  Why is Jones a change in the pricing structure for supply runs?
context: The shadow line between day and night could be seen from the Moon to be drifting across Australia. Evans, who had no watch, thought of the time as a quarter after Australia. But his oxygen was too carefully measured; there was a four-day reserve. Four days reserve—plus one is five—plus sixteen days normal supply equals twenty-one days to live. By the light of this, he reinspected the steam system, and found about three gallons of water frozen in the condenser. The condenser, like all condensers, was a device to convert steam into water, so that it could be reused in the boiler. This boiling lowered the temperature, and the condenser demonstrated its efficiency by quickly freezing the water in the tank. Evans sealed the turbine from the rest of the steam system by closing the shut-off valves. Then, if the pump wasn't blocked by ice, it would return the water to the boiler. Carefully he poured a cup of his drinking water into a pipe that led to the boiler, and resealed the pipe. The water that he had poured into the boiler quickly turned into steam, and the steam turned the generator briefly. For example, because of an order of his stating that there would be no alcoholic beverages within the survey building, the entire survey was assured of a constant supply of home-made, but passably good liquor. Morning to him had no meaning at all, but he thought in the strictest sense that it would be morning on the Moon for another week. It was used mostly, from sun-up to sun-down, to supplement the nuclear power plant. "Bankers' hours don't mean much, at any rate," he said. "I doubt it," Cowalczk answered, "most of these were pinhead size, and they wouldn't go through a suit." "That could hurt," Cowalczk admitted, "but there was only one of them."
output:  It would allow more necessary supplies to reach Earth
options:  He thinks it would save time in writing contracts  He thinks he can make a bigger profit if he has more control  It would allow more necessary supplies to reach Earth  He wants to be able to carry more expensive supplies