To help eliminate the spread of the emerald ash borer, in the Northeast several states require that wood be bought locally (within 50 miles of a campsite). It can also be a citable offense to transport out of state wood. I have never actually known anyone to have been ticketed for it, but there´s always a first.
I used to use charcoal in my brazier all the time. Easy to transport. Maximum heating. Look for natural hardwood charcoal. I used to use a brand called ¨cowboy charcoal.¨ I just transported it in the bag it came in and hid it in the car. I suppose if you really wanted to deep dive, you could cover the bag with a feed sack cover.