There's a huge mobile phone recycling industry with its center of operations in asia (Hong Kong). Old phones are traded in very large bulks and a lot of these w

There's a huge mobile phone recycling industry with its center of operations in asia (Hong Kong). Old phones are traded in very large bulks and a lot of these will have their sim cards still in. I believe the buyers take the phones apart and reuse/resell components, where sims are just one type of component tha can be traded.