My parents, in their 80s, attended this meeting. They have been passive members of the conservative party for decades.
My DF voted leave because he felt the EU we are in now was not the EEC he signed up to. Personally I (and my DB) disagree with him, but he absolutely is not racist, he just (maybe being of the war generation) views an 'independent' Britain as preferable to one that has to follow the way the EU is headed (especially as the EU accounts never get signed off).
Anyway. His view was that the Tory party were elected to the current government on a Brexit means Brexit manifesto and to follow through with the result of the referendum and he was not happy that his MP keeps voting against the proposed deal.