Cosmas-the-Explorer 
Explorer in Training
Blueblood might be a snob but he is also very protective of his family. He reveres Celestia greatly and even he Luna he shows reverence torwards since she is his aunt. Basically he treats most ponies who isn't his family like they're beneath him but for the few ponies who actually are friends with him, he's a loyal friend who would do anything to help them.
Of course anyone else, he considers to be beneath him, including Rarity, who he treated basically as his servant.
Of course anyone else, he considers to be beneath him, including Rarity, who he treated basically as his servant.