Haz-Mat fees are charged by the carrier (that is UPS, FedEx, or other) They end up in the pocket of the carrier for carrying the proper paperwork in the cab of the truck, ensuring the paperwork is with the shipment and all the routing gets filled out and tracked accordingly, and for keeping all that crap on file for any DOT inspection both on the truck and at the office at a later date. Its a lot of BS to keep up with on the carrier's end, plus they have to make sure the driver has a Haz-Mat endorsement on their license. Fees are flat fees per box and posted on the carrier's website if you think you are being overcharged. Trust me, 20.00 a box is cheap. IF you cannot sleep one night, look up all the 49 CFR parts 100-185 they dictate all the regs and other books you have to look in to get the details of said regs.