If I found a company that was reputable, competitive priced and didn't charge HAZMAT "Fees" I'd give them my business FIRST!.
I was involved in this area long before HAZMAT fees existed. I also spent several years doing chemical management at a DOE nuclear site. I know about the Fed regulations for shipping and storage of hazardous materials.
Rules that were in place long, long before any shippers began charging HAZMAT fees. Rules about placarding containers (including the trucks) separation spacing of different materials on the truck, spill containment and other things. Things the shippers are required to do by Federal law. Things they used to do as part of the cost of doing business.
Then, some bright fellow figured out that they could charge the customers extra. because the shipper had to do extra to comply with the LAW, and the customers would pay it. Gripe, but pay it.
Now, here's the part not talked about, its a cash cow for the shippers. It's hugely profitable for them. and they make more money from it than it costs them to comply with the shipping regulations.
Consider this, about shipping and powders and primers. A shipper can put as much material on a truck as fits, and complies with all HAZMAT requirements. The cost to the shipper is what ever it takes to set up the truck to comply with what is being shipped. You could have 500lbs of powder at one end of the trailer and a quarter million primers at the other end and it costs what it costs to do that.
Now, suppose that powder shipment is for 20 different customers, and that primer shipment is for 50 different customers, EACH ONE of them pays an "additional" HAZMAT feed, along with the actual shipping costs.
And suppose there is some other, non gun related hazardous material on the same truck, also in proper containment and spacing, THAT shipment is ALSO paying its own separate HAZMAT fee.....
Think you're just covering the costs imposed by Fed law so the poor shipper can stay in business?? You're not. You're doing a lot more than that, and it goes in the shippers pocket, essentially "for free".