Goggles are usually a must, yes.
There a few folks who don't bother--Junglesmacks, who is some kind of high-powered mutant never even considered for mass production . . . too weird to live, and too rare to die--and Fishy (Fishy gets partial protection from her specs; that's why). But it's better to have them and not need them, than to need them and be miserable. Goggle vents should be covered/few/non-existent. Army Surplus stores are great; I like the $14-20 G.I. Sun/Wind/Dust goggles myself. Others prefer motocross/snowboarder's. Smoked or green lenses are helpful for daytime, because it's bright out and you might not be able to fit your shades underneath. A clear option is nice for night but not a must; there are occasional night duststorms, but most are in the day.
You are unlikely to hassled by law enforcement unless they can see (or smell) something illegal going on, so if you have any illicit inclinations or habits, don't do them, or don't do them in the open, or have anything illegal on you when you leave your camp. Law enforcement does have night-vision and cuddly undercover agents. Last year was fairly nice in terms of interactions with law enforcement, to hear most people tell it (except for the ones caught selling! Huge mistake. Nevada's drug laws do NOT screw around and there is no such thing as Medical Marijuana exemption in NV). Anyway, hassles were apparently few and predictable.
The Survival Guide has a page about how to interact with law enforcement. There's a lot to know with regards to your rights.