Crocs are quantitatively not as good as Birkenstocks. While Crocodiles are certainly wide enough in the toe to accommodate human feet, this is a design cue taken from Birkenstock (the original "Gesundheit Schuh"). The originality they bring is in their material choice: petroleum products. Although I'm a big fan of plastics, let's be honest: they go badly with flesh. Anyone remember their yellow raincoat from grade school? After a twenty-five minute bus ride you were as wet from sweat as you would have been from the rain. My Crocs have the same issue. I can never wear them without socks because they don't (can't) breathe.


Birks, on the other hand are made from cow. Their new slogan should be: "From animals. By animals. For animals." There is no substitute for the magic of leather. Birks breathe, allowing my feet to do the same. So I lose a little bit of versatility (I don't like to wear my Birks at the sandy beach) but I gain both traction and fashion. (Crocs are slippery as well.) 


In conclusion: Birks breathe and aren't slippery. Crocs make noise when I wear them without socks. Cork soles are cooler than foam rubber. Birks are German, Crocs are Chinese. Crocs are better at the beach or poolside, but Birks are better everywhere else.


Birkenstocks win.