on the back of every booster pack i see a code that looks like this...

ZB8BINC
SD33381

What does this mean? Can I redeem the codes for something?

I don't have an authoritative answer for you, but I'd guess it is a way for them to track legitimate packs (i.e., like a serial number). You have the option of sending in packs or cards if you have problems with them. Perhaps they are getting too many such requests and want to start better tracking of packs to assess specific lots that have problems.