Just as the title says, why do manufacturers charge around $100 more for 4.56 gears over the others?

 

I found that alot of the manufactures that list 4.56 gears have not actually put them into production yet or have just started . From what I was told by 2 manufactures (cant remember which ones) said there hasnt been a big demand for that ratio on the jk's ,so maybe lack of demand is the problem.