Terrarium moss...?

I've bought two bags off Sphagnum moss (one's green one's brown). Does the color effect the moss? I'm sure brown means it's dead right?
I've also looked on another forum and found a really old (2008) post on the debate of live or dead moss. People were talking about B&Q being a good place to buy moss. I'm not sure if they were talking B&Q being a place or the DIY site I looked up. The reason I ask is because a 4qt bag of moss is around $10 at my local reptile shop and almost $7 online which adds up quickly since it's such a small bag. The people on the forum were talking about how cheap garden moss is and the way to kill any bugs is to put it in boiling water?
Just wondering what any of you guys think.

Many dry mosses can be rehydrated and brought back to life with proper lighting.

The brown dried sphagnum moss available at petstores really doesn't need replacing that often as long it doesn't become soiled or start to mold. I change mine each time I do a full substrate change as long as it doesn't get poop on it which isn't really that often.