If two people are travelling the bags get checked in under the surname of the person higher up in the alphabetical order.( even if they dont have any status )
That's what I have noticed and they do it unless you specifically tell them not to..I wish they would ask before doing this..
PS: Not a issue specific to EK. Every airline seems to do the same IMHO.Bit painful as my surname begins with a letter towards the end of the alphabet :-(