My Subway didn't have the cups :smh:
Subway's Twitter page will be giving away codes soon and they have QR tags that you can scan to get codes too.
Other than that, I think you can send for one snail mail.
The one thing I can recommend to ANYONE is to call ahead to any of your local stores BEFORE you leave the house... some Subway restaurant just
don't have the cups yet.
As for what you can get from cup/food/chip codes:
http://adventure.subway.com/prizes.htm#rewards
*Each cup code (the one that's specifically printed on the plastic) will get you into the MP; You DON'T have to buy the sandwich/chips if you just want the MP game.
**Each STICKER that comes with the cup (I would assume they either come with the cup as well or you gotta buy the sandwich too; if not, just get the cup) has a code you can also enter in.
THIS CODE give you access to a free dynamic theme, a character skin, a gun, in-game money, or a PSN Home costume.
You can only have one per code.
***The caveat of all these codes is that you can enter multiple times (up to 3 a day per account you set up) to get entries into the tiered prize system as well.
On top of the free MP and in-game swag, you get a chance to get other stuff like:
-3 months of PS+ Plus; $2.99 towards PSN movies/tv shows; or $5 Subway money (Tier 1)
-An armband/journal combo with the UC brand; $50 cash; a copy of UC3 (Tier 2)
-The Collector's Edition of UC3; a PS3 WITH the Collector's Edition; A SONY 36" 3D Bravia TV with 4 sets of glasses/3d sync transmitter/HDMI Cable/PS3/AND the Collector's Edition; $1,000 Cash (Tier 3)