I realize I am late to the game, but this is actually the first time I have encountered Add-on items on Amazon.com. I am currently looking at moving to a new MVNO (more about MVNOs here) and Amazon had a great price on a Net10 Sim card kit, only $0.49. Supposedly this contains the SIM I need to switch to Net10. This is perfect, $0.49 per phone to switch my wife and I to a new network. Deal! Oh wait, I have to spend $25 to get this item... what the...?
So apparently Amazon launched Add-on Items back in July (2012). The idea is, items that are cost prohibitive to ship alone can be added onto regular orders of $25 or more. Neat idea, except maybe I don't need $25 worth of useless crap. Ever think of that Amazon? Or course you did, you just expect people to find another $25 worth of crap to purchase.
The regular (or going) price for the SIM card packs are $9.99 (from Net10) up to $15 (Walmart). So you can see where getting the card for $0.49 would be awesome! So now I am forced to choose, find $24.02 more of something I "need" or suck it up and buy the card locally for a considerable amount more.
Guess I better start shopping.