its not going to help you but it may prevent some one looking for you being killed in a RTA or another air crash.
Apart from anything it saves pissing money up the wall looking for you. At least with a flight following they can zone the search area.
Then hopefully get to you before some dingos have eaten you thus making it easy for your relatives to get a certificate of death and release your estate. Otherwise its 7 years to get things sorted if its the same as the UK.
I am not saying a VFR flight plan is the saving grace but at least talk to some one so they know ruffly where you are and which route you are taking.
Its not for our benefit its for the folk on the grounds benefit.