From what I have read, Chamberlain was by no mean just the old fool with the umbrella who sold out to Hitler at Munich in an deluded effort to "give peace in our time," as he is popularly portrayed. He was desperately trying to buy time as England re-armed for war. At the time he maneuvered Hitler into giving Britain and France a cause for war in September 1939, the Anglo-French forces had the Germans outnumbered and had more and better war materiel. What caused the downfall of Chamberlain was the fact that the underdog Wehrmacht outmaneuvered and outfought the Anglo-French forces during the 1940 Blitzkrieg. Those Hurricanes and Spitfires that won the Battle of Britain were developed and produced on Chamberlain's watch. I have heard it argued that if Churchill's "prescient wisdom" had been heeded, the British would have entered the war with a fleet of 1935 biplanes.
Don't know anything about his family's shoe business, I regret to say.