This is my first post here and after searching for a bit, I don't *THINK* this is a repost.
If you have an alt and you are doing random dungeons, it's possible to get a level 80 into the run to power through the entire thing while you still get your Satchel of Goods.
This is easiest when done with two accounts or with a friend that has an alt around the same level as your own. Preferably your friends alt (or the one you intend on NOT leveling) should be able to queue as a tank or healer to get fast pops.
Once you get a pop and are in the dungeon, have your friend leave the party. At this point, you can either continue on or search for another member using the LFD feature. However, you are also able to invite players of any level into the group. They are able to teleport straight into the instance and can be used to finish the instance.
tl;dr
Get into a dungeon
Get someone to leave
Invite your 80
Boost through the instance
Hopefully *SOMEONE* will fine this useful. Again, if this is a repost, I apologize as I wasn't able to find anything of this sort when searching.