A lot of times companies get a rather large rebate / discount on the back end of these ticket prices. Where it may loook more expensive for the individual ticket in question they may save morein the long run by booking with a preferred airline. There are actually positives to this process such that if you were to work there it makes it easy to consitently book with the same airline and obtain status.

I would prefer this to a company that just always hunts around for the lowest price and books you with all different carriers. IMHO