If you do want to recycle your old Crocs, clearly mark the outside
of the package with “RECYCLE” and mail them to:
1510 Nelson Rd.
Longmont, CO 80501
Since Crocs are lightweight, average estimated postage will be around
$2 (though don’t hold me to that as an ewxact amount.)
Old Crocs are shredded to make padding for children’s playgrounds. Unfortunately, municipal recycling programs don’t recycle Crocs at this time. The company is working on a more expanded recycling program, but they have not released any details
(source modified text from Zappos Daily Shoe Digest)