Prepaid phones & prepaid card refills

Where do prepaid cards for prepaid phones go afterward but to the trash?

Cellphone companies that sell prepaid phones and prepaid cards should offer a card recycling program. Make the cards smaller. Better yet, have an option to have it prepaid online or over the phone – using a different phone to call them, of course. Or even using the same prepaid cellphone, just don’t charge users for refilling their prepaid phones.