Lots of reasons why that could be.. not sure how many manufacterers of old truck glass there are, but i'll bet there is more than one.. i mean, it's glass. Anybody with a pattern and rudementury glass cutting skills can cut it.. not like they have to import it from whoo flungg dung like the majority of the repop parts.
Then there's the loss leader.. hey, I need glass.. and this outfit sells glass really cheap! While i'm ordering my glass from them, i'll pick up the other stuff I need, too.
That other stuff may or may not be as cheap as the other places.. which is how they make up for selling the glass so cheap.
Then there are the reasons Kimberly mentioned.. size of the outfit, shipping to their warehouse costs, amount of volume discount they get from their distributer, etc etc.
Or it could be that they have their own in-house glass shop, or have some guy across town with all the patterns who is happy to 'cut on demand' when they get an order.
