Except when you think about how humans like to put smiley faces on animated objects and such to convey happiness. Now think about it from a different way. How does a fox convey happiness more so than a wagging tail? And those tails are likely not real tails, just decoration.
If you look at their heritage armor set. They even have little bags on their belt shaped and designed like fox tails.
I think someone found a plant in game that looks like that - so TLDR: its a plant.
Right but… we don’t cut other peoples’ faces off and then plaster those things on top of animated objects. That would be morbid!
Why wouldn’t vulpera collect fox tails? They aren’t foxes, just tangentially related to them. We’re related to monkeys, and yet monkey’s paws exist…
Oh and like how the Forsaken hang dead humans from trees as a way of expressing their curiosity about the living? Human skulls being used as candle holders by the peaceful Tauren in their inns?
It’s just expression don’t begrudge them.
Millions of people around the world regularly wear a depiction of an ancient Roman execution device as jewelry.
Vulpera displaying the tails of animals similar to them as a decoration is no more morbid than humans wearing ape/monkey furs in areas where those animals are plentiful.
You think the vulpera traveled across the sea from Vol’dun to Highmountain just to collect wagon decorations?
Vulpera don’t waste anything. I have a feeling that if Forsaken didn’t already have Cannibalize, Vulpera would have gotten it.
“Hey, like my new tent? I made it out of my Aunt Nessie.”
Pirates
Vulpera Pirates…
Humans colllected and wore human scalps.
You’re just weirded out to encounter a race as savage as yourself. 
orcs are just green humans 
Those are the vulpera you didn’t get to meet.
Does anyone know if vulpera can be mages?
OP, it’s quite likely that the bag is a loose sack with a reinforced bottom so it may coincidentally look like fox tail, but there’s probably a stick or something inside to help it maintain its shape. Like if you wanted to keep herbs and plants straight in a bag of dirt, for example.
Its possible that its their dead or just a collection of talismans used to represent the fallen as retrieving tails would be a risky costly endeavour in their hellish environment.
Plus from what I hear from their jokes they get very bored out in the sands so it might’ve just been a cultural habit they picked up among the caravans, it may even be a way for them to convey scent to mark territory…even express an interest in breeding.
Alliance pvp mount Prestigious War Steed has actual heads of enemies hanging from it.
Some psycopaths might.
They might also make a lampshade from it.
I was suddenly reminded of this one episode of Llamas with hats.
But foxes have cat software in dog hardware so… do they really wag their tails when happy?
My cat does. He also stealth ambushes you and tries to eat your leg to let you know that he cares.
But he likes to head-butt, purr, and wag his tail to let you know he’s happy.
That or he’s just trying to see if I’m still alive and whether or not he can eat me now. Could be both.
What, like “come get some tail!”?
Id like to get some tail from meerah for sure…