Jazz shoes are describes by a nytimes.com article as a favorite of the "intelligently offbeat". The genesis of this being a favored style for many non-dancers is in French singer Serge Gainsbourg's search for relief for his sensitive feet. He found the answer in calfskin jazz shoes made by French dance shoe company Repetto. Gainsbourg, also a style icon, inspired for others the shoe's appeal for every day wear. His daughter Charlotte Gainsbourg, actress and fashion house muse has also popularized the shoes.
Serge Gainsbourg
An appeal for these may be a very important factor in footwear: comfort! Though I have yet to try my first pair, that is primarily the reason I am jazzed for jazz shoes. Add to that the unassuming, beatnik vibe and these are comfy casual walking shoes I'd wear and I could care less whether they are truly "in". I need good arch support and the websites ( Dance4Less.com, DancewearSolutions.com) from which I got the pictures below (the first three photos) included that feature in the general description of the comfort of the shoe. Anyway, they supersede crocs in aesthetic appeal of a "comfortable shoe".
Higher-end versions of jazz shoes