i keep them.
3 really good reasons:
1, to track the money i waste. (it's easy to reach hundreds wasted if you are bad with money)
2, if my account gets stolen i can use them to easily provide proof that i am the owner. i had to do this with steam a couple of times. and they are insurance that my account can't never get lost to a thief.
this reason is also valid in other online stores you bought using theese cards, they are always a good proof of ownership\purchase.
3 they are small, they can be easily stored somewhere, i put my steam cards inside my retail pc games
protip: write with a pencil how much money is left in the card, or if it's empty.
--------------------- MERGED ---------------------------
No?
There's even sites online where you can sell unused giftcards. You're probably fine. It's not like when purchasing one you have to give your address or anything. The only exception I can think of is some types of disposable credit cards.
pretty much, but its always good to make them unusable\unreadable related of my second reason of keeping them.
if "your cousin" or "friend" got a hold of your steam cards, they can contact steam and claim ownership of your account..
it's kinda hard to do, but it's possible...
i remember in the past, i am not sure if it's still done nowadays but people when buying\getting stolen accounts they buy cheap shit in them, then use this purchases to claim the account as theirs... some ocasions the original owner can't provide proof of payment (because he didn't kept receipts\spent gift cards) and the theft is "confirmed owner"