It might be a differance in size, but it just fire wood that has been charred, nobody wants to try and provide me charcoal for a 3 day event that might use 10-15 dutch ovens a meal.
I don't have much trouble getting wood.
BTW you can make it at home, get a 55 gallon drum with a lid that bolts down with a band. build a iron stand and fill the barrel up with the desired amount of hardwood. Seal up the drum, wut leave a 1/2 in hole and build a fire under the drum. when the smoke comes out the hole, try to light it till it lights. When the fire in top goes out, drop a 1/2' bolt in the hole and put a hunk of wet clay on top. This will keep the air out and keep the wood from burning up. Put out the fire and wait till the drum is cool to the toch, you have natural charcoal.
This is just a larger scale version of makin' charr cloth fer yer flint and steel.