I always thought that the icons were built into the frame and the rubber was just molded around it, but I'm trying to picture the frame in my head and that doesn't seem too sensible on paper haha.
The icons are stuck on with some form of double sided tape. They are quite easy to remove. Just use your finger nail to get underneath the icon and it comes straight off
Same thing happened to my Half Jacket. I asked Oakley about a replacement icon and this was part of their response, "Unfortunately because Oakley frames are considered one complete part we are unable to replace only one component of the frame." Basically they suggested I send it back for non-warranty repairs.