Its all about the video footage and at the HDRA races most of that comes from the helicopters.
Nick Isenhouer and the at BRO-DOZER team have made some moves to promote themselves and their sponsors so they can hopefully increase their value to their current sponsors and get some new ones too. Its all about name recognition and these guys are "doing it right".
When the chopper flys over them they wont just be another truck on the track. They will be the Nick Isenhouer 1405 truck and everyone will know it.
As an added bonus the go pros they are running will have strategically placed stickers as well so that any go pro footage they submit post race to HDRA for use in the TV show will have sponsor recognition also.
Remember everyone, if you are going into your own pocket to race, you are a sponsor also. So make sure you promote yourself along with the companies who support your racing efforts.