Don't let Craggy Wash sour using BLM land for you. I just finished a 4 month trip staying on BLM land, state parks, national monuments, national parks, etc. including a few days at Craggy Wash. There's a lot of fantastic free dispersed camping on BLM land out there in the country with wide open vistas an no nearby neighbors.
I don't know how far in you went, but I drove half way up the hill to the top away from everyone, and didn't have a bad experience there. There were some nice spots at the top of the hill too. I liked a lot of other BLM areas better, and probably wouldn't go back here though. I actually wished I had stopped around Parker instead because the rock canyon was so much cooler to me than Lake Havatsu area.
I'm certainly not trying to defend that guy's behavior, but I remember it being pretty dusty there. Maybe your rig kicked up a ton of dust that he and his dog had to walk through? and he was trying to convey his displeasure in one gesture? When there's people near the road, I always tried to slow down even more and check the dust cloud behind me to try to minimise it as much as I could to be considerate to them. (Hopefully the guy you referred to wasn't me either! I walked my dog up and down the hill there.)