A friend we met along the TransAmerica was using those clip on platforms with his SPD pedals and was very happy with them. I am tempted to try a pair.
FWIW: I too am very happy with my Crocs for off bike footwear when touring. They aren't optimum for hiking, but were at least OK for a mile or three when my feet were weary of my Sidi MTB shoes. They were easy to step into when going out of the tent. They doubled as shower shoes. They are very light weight.