Cars necessary to everyday life?

No they are not - like addictions we as a society have made them important. We are addicted.

As for Mr Heston. He entertained as an actor, and apart from his gun addiction he had some very personable traits.

A struggling actor buttonholed him and asked for advice - he got into conversation and offered to do an evening at a local theatre The Roses Tewkesbury. I dunno what it did for the actor but the town and the theatre sure benefitted. All for no fee.