It's a road rally, As to the issue of helmets etc. My understanding is that this event is run as a road rally (or endro) which runs under different Motor Sport Association (MSA) rules to that of special stage rallying - the more common events you will see pictures of.
With road rallies the MSA has very strict rules about the cars taking part. Cars have to run devoid of advertising, with only four forward facing lights, strict noise limits and helmets etc are not required. So the cars are not so "in your face" for joe public. The vast majority of road rallies run at night. But every road rally run in the day will be run on private land, farmers fields etc.
Cheers,