I will NEVER use you if you are sitting on a mailbox or blocking the way. I started my personal blacklist.Had to because I was tired of the second you got paid a lot for gear repair you suddenly transformed and disappeared.
I will use an off to the side mount vendor, one in my Covenant, or a normal vendor. Sheesh!!
Edit: Answered with a great deal of humor in between! Thank you - 
huh? i don’t think the npcs read the forums
Those vendors on mounts brutosouars or some thing…or the mammoth peeps. You know the GUYS THAT SIT ON MAILBOXES vying for your business!
I can’t choose the vendors that sit on the side of my dino, bro. Don’t blame the whale, blame the fish hitching a ride!
You do know they don’t get your gold?
Huh? You can use them for free. I’m confused. Or just click the mailbox through them if that’s what you’re after?
It can’t be Sunday already, I’m watching college football.
Yep - I t’aint splaining myself correctly. I give up. Lol… mia culpa
I know this might blow some minds with todays entitlement… but those people aren’t there for you. They are using their mounts near a mailbox for their own personal convenience.
but…they’re using their mounts for them, not for you?
also, whats an edit peeps?
It’s almost like they’re using the auction house on their own mount and need easy access to a mailbox. 
you know you can click the mailbox through their mount, yea?
I agree that the people who stand ON the mailbox are obnoxious. but the ones who stand near it are doing a wow god’s work.
I’m sure some trolls do that on purpose.
Hate doing that! Lol. …pile on, no problem - already goofed up something, though not sure what. Probably just misunderstood something I’ll have to Google or wowhead if I cared enough.
Snort! Zing, nice one 
i don’t think anybody’s piling on, we just don’t know what you’re talking about. the gold you pay to vendors doesn’t go to the player whose mount they’re on.
Oh my!
(This kind of reminds me of … this)
I promise I will NEVER sit on my Brutosaur on top of the Oribos mailbox!
Actually I don’t like using my Brutosaur in Oribos because I just can’t bring myself to dismount and cut people off while they’re using it. So, I’m usually sitting there for about an hour after I’ve finished what I wanted to do. 
P.S. Enjoy the proof that I actually DO watch cat videos on youtube. xD
Or those that are parked on the Dalaran to Org portal with their huge selves! Those we can’t click through to hit the portal. God knows why they sit there so long. They’re active in some capacity, because I’ve seen them there throughout the day when I was farming old dungeons and raids.
point? players don’t even get a fee cut when ppl use thier vendors
They have marshmallow Peeps for every holiday now. I guess it’s a new flavor? 