Okay, since this has been bumped recently, I'll reiterate what I said before in another thread. If you're an enchanter, and decide not to offer to DE for a group, it's your right. However, you're more likely to get disenchanting goods if you are willing to DE. Why do I say this? Simple. You are one of five people rolling each time for the items that drop, if nobody needs them. Each time you roll Greed, you have a 1 in 5 chance of getting an item. Let's use an analogy, and say you're in a group with 5 items that drop that nobody needs, and everyone wants to greed roll for vendor.
Scenario One wrote:
Item 1: Everyone rolls, and you roll a 2. Someone else rolls 68 and wins a pair of blue pants.
Item 2: Everyone rolls, and you roll 53. Someone else rolls 82 and wins a pair of blue pants.
Item 3: Everyone rolls, and you roll 78. Someone else rolls 97 and wins a pair of blue pants.
Item 4: Everyone rolls, and you roll 16. Someone else rolls 85 and wins a pair of blue bracers.
Item 5: Everyone rolls, and you roll 91. Someone else rolls 99 and wins a purple chest piece.
You win nothing in that scenario, and the other people that won something get to vendor it- which probably won't be worth as much as the Dream Shards or Abyss Crystals they might have won. Now, on to another scenario where everyone passes on each item that they don't need, and you pick them up. At the end of the run, you all roll for shards.
Scenario Two wrote:
At the end of the run, everyone rolls for shards.
The tank rolls 82.
Druid healer rolls 97.
Death Knight rolls 85.
Warlock rolls 99.
You roll 91.
The shards are divvied up evenly. The Warlock, having the highest roll, gets the Abyss Crystal. The rest of you get one Dream Shard each.
Granted, you didn't win 4 shards and a crystal- but then, thanks to the random number generator, you have a good chance of not winning each time you roll for an item against your other four party members. When you decide to play nicely with other people, your odds improve. I'd prefer a 3 in 5 chance or even 2 in 5 chance of winning a shard or crystal at the end of a run to a 1 in 5 each time. But maybe that's just me.