I have a 70 undead warlock, a 70 belf hunter and a 34 draenei mage. And from leveling on two different servers I can tell you its completely dependant on the server. On my horde server, people will usually leave eachother alone all though there is of course the lovely random ganking to be found on a pvp server. On my alliance server however, leveling up I have only seen two horde that have not tried to kill me on sight. On both servers Ive met people that have given me fair amounts of gold for helping them with simple things, and those that are complete asshats. On both sides.

Calling someone stuck-up and snobbish and the spouting the reasons why your group is so much better, not only shows your own arrogance, but also your ignorance.

And frankly learning more of the alliance lore as Im leveling, the horde arnt too far off from the alliance in terms of corruption. The alliance are trying to make their best despite the past, as are the horde. Yes they have defias, they screwed up with the stonemasons and the gnomes blew up their own home, but look at the horde. Grimtotem clan, Shadow council, hell the entire forsaken race?

I suggest that you are the one who needs to learn some respect and not judge people solely based on their races in a fantasy game.